Intel Thermostat 315889 002 User Manual

Voltage Regulator Module  
(VRM) and Enterprise Voltage  
Regulator-Down (EVRD) 11.0  
Design Guidelines  
April 2008  
Reference Number: 315889-002  
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Contents  
Applications...............................................................................................................9  
Output Voltage Requirements.................................................................................. 11  
Control Signals ........................................................................................................ 27  
Input Voltage and Current....................................................................................... 33  
Processor Voltage Output Protection....................................................................... 35  
Output Indicators.................................................................................................... 37  
VRM – Mechanical Guidelines................................................................................... 41  
Environmental Conditions........................................................................................ 45  
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Manufacturing Considerations..................................................................................47  
Z(f) Constant Output Impedance Design..................................................................49  
Figures  
2-7  
Six-layer Dual-Core Intel Xeon Processor-Based Server Platform VccP  
2-8  
2-9  
Eight-layer Dual-Core Intel Xeon Processor-Based Server Platform VccP  
Eight-layer Dual-Core Intel Xeon Processor-Based Server Platform VccP  
2-10 Dual-Core Intel Xeon 5000 Series with Intel 5400 Chipsets Platform VccP  
A-4  
Time Domain Responses and Corresponding Fourier Spectra  
A-5  
A-6  
Photo of Motherboard Analyzed Showing High Frequency  
Measured Platform Impedance Profile Showing Change  
Tables  
Impedance Z Measurement Parameter Limits ......................................................18  
LL  
4
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2-6  
2-7  
Recommended Decoupling and Other Specifications for Supported  
Dual-Core Intel Xeon Processor-Based Server/Dual-Core Intel Xeon  
Workstation Platform Processor Decoupling Capacitor Recommendations .................. 24  
...................................................................................................................... 24  
Dual-Core Intel Xeon 7000 Series with Intel 7300 Chipsets Platform  
2-8  
2-9  
2-10 Dual-Core Intel Xeon 5000 Series with Intel 5400 Chipsets Platform  
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Revision History  
Rev #  
Description  
Rev. Date  
001  
002  
Initial Release  
November 2006  
General- Update Harpertown and Wolfdale-DP to public names  
Table 2-3 correction - Loadline ID codes for 5400/5200 series processors  
April 2008  
6
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The following table lists the revision schedule based on revision number and development stage of the  
product.  
Revision  
Project Document State  
Projects Covered  
0.5  
Preliminary Targets  
HW, SW  
HW, SW  
HW, SW  
HW, SW  
HW Only  
HW Only  
HW Only  
HW Only  
HW Only  
0.5 to 0.9  
1.0  
Updates to Most Recent Update or 0.5  
Design Frozen  
1.0 to 1.5  
1.5  
Updates to Most Recent Update or 1.0  
Preliminary Validation Data (Doc-Dependent)  
Updates to Most Recent Update or 1.5  
(Optional) Final Validation Data (Doc-Dependent)  
Updates to Most Recent Update or 1.75  
Launch Documents  
1.6 to 1.75  
1.75  
1.76 to 1.9  
Launch  
Note: Not all revisions may be published.  
§
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Applications  
1 Applications  
1.1  
Introduction and Terminology  
This document defines the DC-to-DC converters to meet the processor power  
Table 1-1.  
VRM/EVRD 11.0 Supported Platforms and Processors  
Dual-Core Intel® Xeon® 5000 Sequence Platform with Intel® 5000P Express Chipset, Intel® 5000V  
Chipset, Intel® 5000X Chipset, Intel® 5100 Chipset, Intel® 5400A Chipset, or Intel® 5400B Chipset  
®
®
®
®
®
®
Dual-Core Intel Xeon Processor Dual-Core Intel Xeon Processor  
5000 Series 5100 Series  
Quad-Core Intel Xeon  
processor 5300 Series  
®
®
®
®
Dual-Core Intel Xeon Processor Quad-Core Intel Xeon Processor  
5200 Series 5400 Series  
Dual-Core Intel® Xeon® Processor 7000 Sequence-Based Platform with Intel® 7300 Chipset  
®
®
®
®
Dual-Core Intel Xeon Processor Quad-Core Intel Xeon processor  
7200 Series 7300 Series  
The requirements in this document will focus primarily on the Enterprise processors  
®
®
®
based on Dual-Core Intel Xeon Processor-based Server and Quad-Core Intel  
®
Xeon Processor-based Server/Workstation platforms. Some requirements will vary  
according to the needs of different computer systems and processors. The intent of this  
document is to define the electrical, thermal and mechanical design specifications for  
VRM/EVRD 11.0.  
VRM – The voltage regulator module (VRM) designation in this document refers to a  
voltage regulator that is plugged into a baseboard via a connector or soldered in with  
signal and power leads, where the baseboard is designed to support more than one  
processor. VRM output requirements in this document are intended to match the needs  
of a set of microprocessors.  
EVRD – The enterprise voltage regulator down (EVRD) designation in this document  
refers to a voltage regulator that is permanently embedded on a baseboard. The EVRD  
output requirements in this document are intended to match the needs of a set of  
microprocessors. EVRD designs are only required to meet the specifications of a  
specific baseboard and thus must meet the specifications of all the processors  
supported by that baseboard.  
‘1’ – In this document, refers to a high voltage level (V  
and V ).  
IH  
OH  
‘0’ – In this document, refers to a low voltage level (V and V ).  
OL  
IL  
‘X’ – In this document, refers to a high or low voltage level (Don’t Care).  
‘#’ – Symbol after a signal name in this document, refers to an active low signal,  
indicating that a signal is in the asserted state when driven to a low level.  
The specifications in the respective processors’ Electrical, Mechanical, and Thermal  
Specifications (EMTS) documents always take precedence over the data provided in  
this document.  
VRM/EVRD 11.0 incorporates functional changes from prior VRM and EVRD design  
guidelines:  
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Applications  
• New power-on sequence  
• Extended VR 10.x VID table with a 7th bit for 6.25 mV resolution and 0.83125 V to  
1.6 V range, only 12.5 mV resolution will be used in Dual-Core Intel Xeon  
Processor-Based Platform and Intel E8500 platforms.  
• Support for a separate additional VR 11.0 VID table with a 8-bit table and 6.25 mV  
resolution with a 31.25 mV to 1.6 V VID range, only 12.5 mV resolution will be  
used in Dual-Core Intel Xeon Processor-Based Servers and Intel E8500 platforms  
with a VID setpoint range of 0.850 V to 1.6 V.  
• Tighter DC load line tolerance from ±20 mV to ±15 mV  
Table 1-2.  
Guideline Categories  
Guideline Categories  
An essential feature of the design that must be supported to ensure correct processor and  
VRM/EVRD functionality.  
REQUIRED:  
A feature to ensure correct VRM/EVRD and processor functionality that can be supported  
using an alternate solution. The feature is necessary for consistency among system and  
power designs and is traditionally modified only for custom configurations. The feature may  
be modified or expanded by system OEMs, if the intended functionality is fully supported.  
EXPECTED:  
A feature that adds optional functionality to the VRM/EVRD and therefore is included as a  
PROPOSED:  
design target. May be specified or expanded by a system OEMs.  
§
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Output Voltage Requirements  
2 Output Voltage Requirements  
2.1  
Voltage and Current - REQUIRED  
There will be independent selectable voltage identification (VID) codes for the core  
voltage regulator. The VID code is provided by the processor to the VRM/EVRDs, which  
will determine a reference output voltage, as described in Section 3.2. As previously  
mentioned, the VR 11.0 controller will support two VID tables:  
1. An extended 7-bit VR 10.x table, ranging from 0.83125 V to 1.6 V  
2. An 8-bit VR11.0 linear table ranging from 0.03125 V to 1.6 V (usable range 0.5 V-  
1.6 V).  
For Dual-Core Intel Xeon Processor 7000/7100/7200/5000/5100/5200 Series -based  
servers and Quad-Core Intel Xeon Processor 7300/5300/5400 Series -based servers/  
workstations, the VID bits utilization will be as shown in the table below. Section 2.2  
and Section 2.3 specify deviations from the VID reference voltage.  
Table 2-1.  
Processor VID signal implementation  
VID Signals used  
by Processor and  
routed to VR with  
Pull-Up resistors  
Processor Supported  
Notes  
Dual-Core Intel® Xeon®  
Processor 7000/7100 Series  
processor  
VR10.2 mode; VID6 is not driven on the processor  
package (socket 604), but should be routed on the VR  
side with a pullup resistor; VR’s VID7 to be pulled  
Low.  
VID[4:0,5]  
(VID4=MSB  
VID5=LSB)  
Dual-Core Intel® Xeon®  
Processor 5000 Series  
VR10.2 mode; Land AM5 (equivalent to platform  
signal VID6) is not driven on the processor package,  
but still routed to VID6 on VR side with a pullup  
resistor; VR’s VID7 to be pulled Low.  
VID[4:0,5]  
(VID4=MSB  
VID5=LSB)  
Dual-Core Intel® Xeon®  
Processor 5100 Series, Quad-  
Core Intel® Xeon® Processor  
5300 Series, Dual-Core  
Intel® Xeon® Processor  
5200 Series, or Quad-Core  
Intel® Xeon® Processor  
5400 Series processors  
VR11.0 mode; Land AM2 (equivalent to platform  
signal VID0) is connected to VSS on the processor  
package, and routed to VID0 on VR side with a pullup  
resistor; VR’s VID7 to be pulled Low.  
VID[6:1]  
VID[6:1]  
Quad-Core Intel(R) Xeon(R)  
Processor 7300 Series &  
Dual-Core Intel(R) Xeon(R)  
Processor 7200 Series  
processors  
VR11.0 mode; VID0 is not driven on the processor  
package (socket 604P), but should be routed on the  
VR side and pulled Low; VR’s VID7 to be pulled Low.  
The load line tolerance in Section 2.2 shows the relationship between Vcc and Icc at the  
die of the processor.  
The VRM/EVRD 11.0 is required to support the following:  
• A maximum continuous load current (ICCTDC) of 130 A.  
• A maximum load current (ICCMAX) of 150 A peak.  
• A maximum load current step (ICCSTEP), within a 1 µs period, of 100 A.  
• A maximum current slew rate (dICC/dt) of 1200 A/µs at the lands of the processor.  
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Output Voltage Requirements  
The continuous load current (ICCTDC) can also be referred to as the Thermal Design  
Current (TDC). It is the sustained DC equivalent current that the processor is capable  
of drawing indefinitely and defines the current that is used for the voltage regulator  
temperature assessment. At TDC, switching FETs may reach maximum allowed  
temperatures and may heat the baseboard layers and neighboring components. The  
envelope of the system operating conditions, establishes actual component and  
baseboard temperatures. This includes voltage regulator layout, processor fan  
selection, ambient temperature, chassis configuration, etc. To avoid heat related  
failures, baseboards should be validated for thermal compliance under the envelope of  
the system’s operating conditions. It is proposed that voltage regulator thermal  
protection be implemented for all designs (Section 6.2).  
The maximum load current (ICCMAX) represents the maximum peak current that the  
processor is capable of drawing. It is the maximum current the VRM/EVRD must be  
electrically designed to support without tripping any protection circuitry.  
The maximum step load current (IccStep) is the max dynamic step load that the  
processor is expected to impose on its Vcc power rail within the Iccmin and Iccmax  
range, where the Iccmin is the processor’s min load, constituted by its leakage current.  
The amount of time required by the VR to supply current to the processor is dependent  
on the processor’s operational activity. As previously mentioned, the processor is  
capable of drawing IccTDC indefinitely; therefore, the VR must be able to supply  
(ICCTDC) indefinitely. Refer to Figure 2-1 for the time durations required by the VR to  
supply current for various processor loads.  
It is expected that the maximum load current (ICCMAX) can be drawn for periods up to  
10 ms. Further, it is expected that the load current averaged over a period of  
100 seconds or greater, will be equal to or less than the thermal design current  
(ICCTDC).  
Figure 2-1. VRM/EVRD 11.0 Load Current vs. Time  
Icc MAX  
Icc TDC  
0.01  
0.10  
1.00  
10.00  
100.0  
1000.0  
Time Duration (s)  
Table 2-2 shows the ICC guidelines for any flexible motherboard (FMB) frequencies  
supported by the VRM/EVRD 11.0 in Table 1-1. For designers who choose to design  
their VR thermal solution to the ICCTDC current, it is recommended that voltage  
regulator thermal protection circuitry be implemented (see Section 6.2).  
12  
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Output Voltage Requirements  
Table 2-2.  
Icc Guidelines  
ICCTDC  
(A)  
ICCMAX  
(A)  
ICCSTEP  
(A)  
Processor  
Notes  
®
®
Dual-Core Intel Xeon processor 7000 sequence FMB  
130  
115  
130  
100  
70  
150  
135  
150  
115  
90  
100  
100  
90  
76  
40  
30  
25  
70  
50  
35  
37  
21  
36  
67  
68  
65  
60  
78  
72  
72  
54  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
1, 2  
®
®
Dual-Core Intel Xeon 7100 series processor FMB  
®
®
Dual-Core Intel Xeon Processor 5000 Series FMB  
®
®
Dual-Core Intel Xeon Processor 5000 Series MV/667 FMB  
®
®
Dual-Core Intel Xeon Processor X5160 Series Performance FMB  
®
®
Dual-Core Intel Xeon Processor E5100 Series FMB  
65  
75  
®
®
Dual-Core Intel Xeon Processor L5148/5138/5128 Series FMB  
35  
45  
®
®
Quad-Core Intel Xeon processor X5300 Series Performance FMB  
110  
70  
125  
90  
®
®
Quad-Core Intel Xeon processor E5300 Series FMB  
®
®
Quad-Core Intel Xeon processor L5300 Series-LV FMB  
50  
60  
®
®
Dual-Core Intel Xeon Processor X5200 Series  
70  
90  
®
®
Dual-Core Intel Xeon Processor E5200 (  
60  
75  
®
®
Dual-Core Intel Xeon Processor L5200 Series  
38  
50  
®
®
Quad-Core Intel Xeon Processor X5482  
130  
110  
80  
150  
125  
102  
60  
®
®
Quad-Core Intel Xeon Processor X5400 Series  
®
®
Quad-Core Intel Xeon Processor E5400 Series  
®
®
Quad-Core Intel Xeon Processor L5400 Series  
50  
®
®
Quad-Core Intel Xeon Processor X7300 Series  
110  
75  
130  
90  
®
®
Quad-Core Intel Xeon Processor E7300 Series  
®
®
Dual-Core Intel Xeon Processor 7200 Series  
75  
90  
®
®
Quad-Core Intel Xeon Processor L7300 Series  
50  
60  
Notes:  
1.  
These values are either pre-silicon or the latest known values and are subject to change. See the respective  
Processor’s Electrical, Mechanical, and Thermal Specifications (EMTS) for the latest IccTDC and IccMAX  
specifications.  
2.  
3.  
4.  
5.  
FMB = Planned Flexible Motherboard guideline for processor end-of-life.  
Voltage regulator thermal protection circuitry should not trip for load currents greater than ICCTDC  
For platforms designed to support several processors, the highest current value should be used.  
For platforms designed to support a single specific processor, only use that processor’s current  
requirements.  
2.2  
Load Line Definitions - REQUIRED  
To ensure processor reliability and performance, platform DC and AC transient voltage  
regulation must be contained within the VCCMIN and the VCCMAX die load line  
boundaries, except for short burst transients above the VCCMAX as specified in  
Section 2.4. Die load line compliance must be guaranteed across 3-sigma component  
manufacturing tolerances, thermal variation and age degradation. The following load  
line contains static and transient voltage regulation data as well as maximum and  
minimum voltage levels. It is required that the regulator’s positive and negative  
differential remote sense pins be connected to both the VCC_DIE_SENSE, VSS_DIE_SENSE,  
VCC_DIE_SENSE2 and VSS_DIE_SENSE2 pin pairs of the processor socket, see Figure 3-1.  
The prefix VCC is designated for the positive remote sense signal and the VSS prefix for  
the negative remote sense signal.  
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Output Voltage Requirements  
The upper and lower load lines represent the allowable range of voltages that must be  
presented to the processor. The voltage must always stay within these boundaries for  
proper operation of the processor. Operating above the VCCMAX load line limit will result  
in higher processor operating temperature, which may result in damage or a reduced  
processor lifespan. Processor temperature rise from higher functional voltages may  
lead to dynamic operation to low power states, which directly reduces processor  
performance. Operating below the VCCMIN load line limit will result in minimum voltage  
violations, which will result in reduced processor performance, system lock up, “blue  
screens” or data corruption.  
For load line validation information, please refer to the LGA771-V2 Voltage Test Tool  
User’s Guide.  
Figure 2-2 and Figure 2-2 shows the load line voltage offsets and current levels based  
on the VID specifications for the core regulator.  
The encoding in Table 2-2 for the load lines is valid for the range of load current from  
0 A to 150 A. The VID_Select, load line 1 (LL1), and load line 0 (LL0) control signals  
from Section 3.4, form a 3-bit load line selection and will be used to configure the VRM/  
EVRD to supply the proper load lines for the platforms in Table 1-1. Refer to Figure 6-1  
for additional encoding requirements for VRMs. For implementation of VID_Select, LL0,  
and LL1 on the baseboard refer to the appropriate platform design guidelines. The  
VID_Select control signal will select the appropriate VR10 or VR11 table and remap the  
external VID [6:0] pins to the appropriate DAC input. This line will be pulled up  
externally to the VTT rail (1.1 V/1.2 V ± 5%) via a recommended 4.7 kΩ resistor on the  
baseboard and will be programmed by the processor package. The processor does not  
support 5 V or 12 V levels and these should not be used. The VID_Select signal should  
be logic low or tied to ground for extended VR10 table selection. A logic high will  
indicate a VR11 table selection. The VID_Select will not toggle during normal operation.  
.
Table 2-3.  
VID_Select, LL1, LL0 Codes (Sheet 1 of 2)  
VID  
Table Select  
VID_  
LL1  
LL0  
Load Line / Processors  
1.25 mΩ; Reserved  
0
0
0
0
0
1
1.25 mΩ; Dual-Core Intel® Xeon® Processor 5000 Series / MV  
processor LGA771 die Load Line  
1.25 mΩ; Dual-Core Intel® Xeon® processor 7000 series / Dual-Core  
Intel® Xeon® 7100 series processor mPGA604 die Load Line  
0
1
0
Reserved  
0
1
1
0
1
0
1.00 mΩ; Reserved  
1.25 mΩ; Dual-Core Intel® Xeon® Processor 5100 Series, Dual-Core  
Intel® Xeon® Processor 5200 Series, Quad-Core Intel® Xeon®  
Processor 5400 Series, Dual-Core Intel® Xeon® Processor 7200  
Series, Quad-Core Intel® Xeon® Processor 7300 Series  
1
0
1
1.50 mΩ; Reserved  
1
1
1
0
1.25 mΩ; Quad-Core Intel Xeon processor 5300 Series  
1
1
VID  
Table Select  
VID_  
LL1  
LL0  
VCC Tolerance / Die Load Line  
Units  
Notes  
14  
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Output Voltage Requirements  
Table 2-3.  
VID_Select, LL1, LL0 Codes (Sheet 2 of 2)  
VID  
VID_  
LL1  
LL0  
Load Line / Processors  
Table Select  
VccMAX =  
VccMIN =  
VccMAX =  
VccMIN =  
VccMAX =  
VccMIN =  
VccMAX =  
VccMIN =  
VccMAX =  
VccMIN =  
VccMAX =  
VccMIN =  
VccMAX =  
VccMIN =  
VccMAX =  
VccMIN =  
VID (V) –1.25 mΩ • Icc (A)  
0
0
0
V
V
V
V
V
V
V
V
3
VID (V) –1.25 mΩ • Icc (A) –30 mV  
VID (V) –1.25 mΩ • Icc (A)  
VID (V) –1.25 mΩ • Icc (A) –30 mV  
VID (V) –1.25 mΩ • Icc (A)  
VID (V) –1.25 mΩ • Icc (A) –30 mV  
reserved  
0
0
0
1
1
1
0
1
1
0
0
1
1
1
0
1
0
1
0
1
2, 3  
1, 3  
3, 4  
1, 3  
1, 3  
1, 3  
1, 3  
reserved  
VID (V) –1.00 mΩ • Icc (A)  
VID (V) –1.00 mΩ • Icc (A) –30 mV  
VID (V) –1.25 mΩ • Icc (A)  
VID (V) –1.25 mΩ • Icc (A) –30 mV  
VID (V) –1.50 mΩ • Icc (A)  
VID (V) –1.50 mΩ • Icc (A) –30 mV  
VID (V) –1.25 mΩ • Icc (A)  
VID (V) –1.25 mΩ • Icc (A) –30 mV  
1
Notes:  
1.  
2.  
The Vcc values are the expected voltage measured at the processor die.  
The Dual-Core Intel® Xeon® 7100 series / Dual-Core Intel® Xeon® processor 7000 sequence entry is  
required for backward compatibility for VR ‘modules’ only using the EVRD/VRM 10.2, but the VRM11.0  
should be backward compatible with VRM10.2 platforms, as modular VRs can be transferred from one  
platform to another.  
3.  
For VRM 11.0 mode, VRM_Pres# and VR_ID# should be held LOW for all combinations as described in  
2.3  
Voltage Tolerance - REQUIRED  
The voltage ranges shown in Section 2.2 include the following tolerances:  
• Initial DC output voltage set-point error.  
• Output ripple and noise.  
• No-load offset centering error.  
• Current sensing and droop errors.  
• Component aging affect.  
• Full ambient temperature range and warm up.  
• Dynamic output changes from minimum-to-maximum and maximum-to-minimum  
load should be measured at the point of regulation. When measuring the response  
of the die voltage to dynamic loads, use the VCC_DIE_SENSE and VSS_DIE_SENSE  
or VCC_DIE_SENSE2 and VSS_DIE_SENSE2 pins on the processor socket with an  
oscilloscope set to a DC to 20-100 MHz bandwidth limit and with probes that are  
1.5 pF maximum and 1 MW minimum impedance.  
• Variations of the input voltage.  
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Output Voltage Requirements  
2.4  
Processor VCC Overshoot - REQUIRED  
The VRM/EVRD 11.0 is permitted short transient overshoot events where Vcc exceeds  
the VID voltage when transitioning from a high-to-low current load condition  
(Figure 2-2). This overshoot cannot exceed VID + VOS_MAX. The overshoot duration,  
which is the time that the overshoot can remain above VID, cannot exceed TOS_MAX.  
These specifications apply to the processor die voltage as measured across the remote  
sense points and should be taken with the oscilloscope bandwidth setting limited to  
20 MHz or 100 MHz, depending what is supported by your particular scope (with  
20 MHz preference).  
• VOS_MAX = Maximum overshoot voltage above VID = 50 mV  
• TOS_MAX = Maximum overshoot time duration above VID = 25 µs  
Figure 2-2. Processor Vcc Overshoot Example Waveform  
VOS  
VID + 0.050  
VID - 0.000  
TOS  
0
5
10  
15  
20  
25  
Time [us]  
TOS: Overshoot time above VID  
VOS: Overshoot voltage above VID  
2.5  
Impedance vs. Frequency - EXPECTED  
Vcc power delivery designs can be susceptible to resonance phenomena capable of  
creating droop amplitudes that violate the load line specification. This is due to the  
frequency varied PCB, output decoupling and socket impedances from the power plane  
layout structures. Furthermore, these resonances may not be detected through  
standard time domain validation and require engineering analysis to identify and  
resolve.  
Impedance vs. Frequency, Z(f) performance simulations of the power delivery network  
is a strongly recommended method to identify and resolve these impedances, in  
addition to meeting the time domain load line in Section 2.2 and Section 2.3. The  
decoupling selection needs to be analyzed to ensure that the impedance of the  
decoupling is below the load line target up to the FBREAK (2 MHz) frequency as defined  
in Figure 2-3. Frequency domain load line and overshoot compliance is expected across  
the 0 Hz to FBREAK bandwidth. The power delivery frequency response is largely  
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dependent upon the selection of the bulk capacitors, ceramic capacitors, power plane  
routing and the tuning of the PWM controller’s feedback network. This analysis can be  
done with LGA771-V2 VTT tool impedance testing or through power delivery simulation  
if the designer can extract the parasitic resistance and inductance of the power planes  
on the motherboard along with good models for the decoupling capacitors.  
Measured power delivery impedance should be within the tolerance band shown in  
Figure 2-3. The tolerance band is defined for the VTT impedance measurement only.  
For load line compliance, time domain validation is required and the VR tolerance band  
must be met at all times. Above 500 kHz, the minimum impedance tolerance is not  
defined and is determined by the MLCC capacitors required to get the ESL low enough  
to meet the load line impedance target of the FBREAK frequency. At 700 kHz, the ZMAX  
tolerance drops to the load line target impedance. Any resonance point that is above  
the ZMAX line needs to be carefully evaluated with the time domain method by applying  
transient loads at that frequency and looking for VMAX or VMIN violations. Maintaining  
the impedance profile up to FBREAK is important to ensure the package level decoupling  
properly matches the motherboard impedance. After FBREAK, the impedance  
measurement is permitted to rise at an inductive slope. The motherboard VR designer  
does not need to design for frequencies over FBREAK as the Intel Microprocessor  
package decoupling takes over in the region above FBREAK.  
Each of these design elements should be fully evaluated to create a cost optimized  
solution, capable of satisfying the processor requirements. Experimental procedures for  
measuring the Z(f) profile will be included (shortly) in the next revision of the  
EVRD_VRM11_0_LL_dVID LGA771_775-V2 VTT Tester-UG.pdf Test Methodology User’s  
Guide using the VTT. Additional background information regarding the theory of  
operation is provided in Appendix A.  
Figure 2-3. Power Distribution Impedance vs. Frequency  
Zone 2  
Zone 1  
Output Filter  
Bulk & MLCC  
PWM Droop control  
& compensation BW  
ZLL Max  
Z target = ZLL  
ZLL Min  
Zone 3  
Inductive effects  
MLCC ESL +  
Socket  
Hz  
Fbreak  
VR BW  
500 kHz  
700 kHz  
Notes:  
1.  
Zone 1 is defined by the VR closed loop compensation bandwidth (VR BW) of the voltage regulator.  
Typically 30-40 kHz for a 300 kHz voltage regulator design  
2.  
Zones 2 & 3 are defined by the output filter capacitors and interconnect parasitic resistance and  
inductance. The tolerance is relaxed over 500 kHz allowing the VR designer freedom to select output filter  
capacitors. The goal is to keep Z(f) below ZLL up to FBREAK (2 MHz) and as flat as practical, by selection of  
bulk cap values, type and quantity of MLCC capacitors. The ideal impedance would be between ZLL and  
ZLLMin, but this may not be achieved with standard decoupling capacitors.  
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3.  
See Section 2.5 and Table 2-4, Impedance Measurement parameters and definitions  
Table 2-4.  
Impedance Z Measurement Parameter Limits  
LL  
1
2
3
Processor  
Notes  
ZLL  
ZLLMax  
ZLLMin  
Fbreak  
®
®
Dual-Core Intel Xeon Processor 5000 Series  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.45 mΩ  
1.05 mΩ  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
2.0 MHz  
®
®
Dual-Core Intel Xeon Processor 5000 Series MV  
1.511 mΩ  
1.583 mΩ  
1.583 mΩ  
1.917 mΩ  
1.49 mΩ  
0.989 mΩ  
0.917 mΩ  
0.92 mΩ  
®
®
Dual-Core Intel Xeon Processor X5100 Series -Perf.  
®
®
Dual-Core Intel Xeon Processor E5100 Series  
®
®
Dual-Core Intel Xeon Processor L5100 Series LV  
0.583 mΩ  
1.01 mΩ  
®
®
Quad-Core Intel Xeon processor X5300 Series -Perf.  
®
®
Quad-Core Intel Xeon processor E5300 Series  
1.583 mΩ  
1.750 mΩ  
1.583 mΩ  
1.673 mΩ  
1.850 mΩ  
1.450 mΩ  
1.490 mΩ  
1.544 mΩ  
1.750 mΩ  
1.481 mΩ  
1.583 mΩ  
1.583 mΩ  
1.750 mΩ  
0.917 mΩ  
0.750 mΩ  
0.917 mΩ  
0.827 mΩ  
0.650 mΩ  
1.050 mΩ  
1.010 mΩ  
0.956 mΩ  
0.750 mΩ  
1.019 mΩ  
0.917 mΩ  
0.917 mΩ  
0.750 mΩ  
®
®
Quad-Core Intel Xeon processor L5300 Series- LV  
®
®
Dual-Core Intel Xeon Processor X5200 Series -Perf.  
®
®
Dual-Core Intel Xeon Processor E5200 Series  
®
®
Dual-Core Intel Xeon Processor L5238 Series  
®
®
Quad-Core Intel Xeon processor X5482 Series - Perf. 1.25 mΩ  
®
®
Quad-Core Intel Xeon processor X5400 Series - Perf. 1.25 mΩ  
®
®
Quad-Core Intel Xeon processor E5400 Series  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
1.25 mΩ  
®
®
Quad-Core Intel Xeon processor L5400 Series  
®
®
Quad-Core Intel Xeon processor X7300 Series - Perf  
®
®
Quad-Core Intel Xeon processor E7300 Series  
®
®
Dual-Core Intel Xeon Processor 7200 Series  
®
®
Quad-Core Intel Xeon processor L7300 Series  
Notes:  
1.  
2.  
Z
Z
is the target impedance for each processor and Z(f) value coincides with it’s Load Line slope.  
LL  
LLMAX  
is the max allowed Z tolerance, which still fits within the VccMax and VccMin Load Line limits listed  
LL  
in Table 2-3; Z  
IccMax.  
is specific for each processor due to a specific combination of its Load Line value and  
LLMAX  
3.  
Z
LLMIN is the min allowed Z tolerance, which still fits within the VccMax and VccMin Load Line limits listed  
LL  
in Table 2-3; Z  
IccMax.  
is specific for each processor due to a specific combination of its Load Line value and  
LLMIN  
2.6  
2.7  
Stability - REQUIRED  
The VRM/EVRD needs to be unconditionally stable under all specified output voltage  
ranges, current transients of any duty cycle, and repetition rates of up to 2 MHz. The  
VRM/EVRD should also be stable under a no load condition.  
Processor Power Sequencing - REQUIRED  
The VRM/EVRD must support platforms with defined power-up sequences. Figure 2-4  
shows a timing diagram of the power-on sequencing requirements. Timing parameters  
for the power-on sequence are listed in Table 2-5.  
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Figure 2-4. Power-On Sequence Timing Diagram  
BCLK [1:0]  
(for reference only)  
PWM Vcc  
(5V/12V)  
Tf  
Ta  
VTT  
VTT_PWRGD  
OUTEN  
VID_SELECT  
(pulled up to VTT)  
Tg  
Tc  
VBOOT=1.1V  
Vcc_CPU  
Te  
Td  
Tb  
VR_READY  
VID code read by PWM at the end of Tc  
VID valid  
VID bits  
/ BSEL[2:0]  
CPU_PWGOOD (from platform, for reference only)  
RESET#  
(for reference only)  
VCCPLL  
(for reference only)  
Notes:  
1.  
2.  
3.  
VTT_PWRGD can be designed to be driving directly the OUTEN input.  
Tb and Td voltage slopes are determined by soft start logic of the PWM controller.  
Vboot is a default power-on Vcc (Core) value. Upon detection of a valid Vtt supply, the PWM controller is to  
regulate to this value until the VID codes are read. The Vboot voltage is 1.1 V  
VTT is the processor termination regulator’s output voltage and the VTT_PWRGD is the VTT regulator’s  
power good status indicator.  
4.  
5.  
6.  
Unless otherwise noted, all specifications in this table apply to all processor frequencies.  
This specification requires that the VID signals be sampled no earlier than 10 µs after VCC (at VCC_BOOT  
voltage) and VTT are stable.  
Parameter must be measured after applicable voltage level is stable. “Stable” means that the power supply  
is in regulation as defined by the minimum and maximum DC/AC specifications for all components being  
powered by it.  
7.  
8.  
The maximum PWRGOOD rise time specification denotes the slowest allowable rise time for the processor.  
Measured between (0.3 * VTT) and (0.7 * VTT).  
Table 2-5.  
Startup Sequence Timing Parameters (Sheet 1 of 2)  
Timing  
Min  
Default  
Max  
Remarks  
Ta =  
If the actual timing exceeds 2ms, the  
VTT VR must be capable of  
supporting full Itt surge current  
requirement per Proc’s latest EMTS  
PWM Vcc & Vtt to OUTEN delay  
time  
0
2.0 ms  
5.0 ms  
Tb =  
Vboot rise time  
Programmable soft start ramp;  
Measured from 10-90% of slope  
0.05 ms1  
0.05 ms1  
0.5 ms  
10.0 ms  
3.0 ms  
Tc =  
Vboot to VID valid delay time  
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Table 2-5.  
Startup Sequence Timing Parameters (Sheet 2 of 2)  
Timing  
Min  
Default  
Max  
Remarks  
Td =  
Programmable soft start ramp;  
Measured from 10-90% of slope  
0
0.25 ms  
2.5 ms  
VccCPU rise time to final VID  
Te =  
0.05 ms  
0.05 ms  
0
3.0 ms  
10.0 ms  
5.0 ms  
VccCPU to VR_READY  
assertion time  
Tf =  
Vtt rise time  
Measured from 10-90% of slope  
Tg =  
OUTEN to Vcc_CPU rising -  
delay time  
Note:  
1.  
Minimum delays must be selected in a manner which will guarantee compliance to voltage tolerance  
specifications.  
2.8  
Dynamic Voltage Identification (D-VID) -  
REQUIRED  
VRM/EVRD 11.0 supports dynamic VID across the entire VID table. The VRM/EVRD  
must be capable of accepting voltage level changes of 12.5 mV steps every 5 µs. The  
low voltage state will be maintained for at least 50 µs. The worst case settling time,  
including line-to-line skew, for the seven VID lines is 400 ns. The VID inputs should  
contain circuitry to prevent false tripping or latching of VID codes during the settling  
time.  
During a transition, the output voltage must be between the maximum voltage of the  
high range (“A” in Figure 2-5) and the minimum voltage of the low range (“B”). The  
VRM/EVRD must respond to a transition from VID-low to VID-high by regulating its Vcc  
output to the range defined by the new final VID code, within 50 µs of the final step.  
The time to move the output voltage from VID-high to VID-low will depend on the PWM  
controller design, the amount of system decoupling capacitance, and the processor  
load.  
Figure 2-5 shows operating states as a representative processor changes levels. The  
diagram assumes steady state, maximum current during the transition for ease of  
illustration; actual processor behavior allows for any dIcc/dt event during the  
transitions, depending on the code it is executing at that time. In the example, the  
processor begins in a high-load condition. In transitions 1-2 and 2-3, the processor  
prepares to switch to the low-voltage range with a transition to a low load condition,  
followed by an increased activity level. Transition 3-4 is a simplification of the multiple  
steps from the high-voltage load line to the low-voltage load line. Transition 4-5 is an  
example of a response to a load change during normal operation in the lower range.  
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Figure 2-5. Processor Transition States  
2
VID High Load Line  
A
3
Icc-max  
1
5
VID Low Load Line  
4
B
Figure 2-6 is an example of dynamic VID. The diagram assumes steady state, constant  
current during the dynamic VID transition for ease of illustration; actual processor  
behavior allows for any dIcc/dt during the transitions, depending on the code it is  
executing at that time. Note that during dynamic VID, the processor will not output VID  
codes that would disable the voltage regulator output voltage.  
Figure 2-6. Dynamic VID Transition States Illustration  
ext.  
VR11  
table  
VR10  
table  
36 VID steps @ 5 s each step = 180us  
400ns  
VID 1 VID 5  
VID 2 VID 0  
worst case VID  
settling time  
VID 3 VID 1  
VID 4 VID 2  
VID 5 VID 3  
VID 6 VID 4  
Note: VR11 table – VID 0 and extended VR10 table – VID 6 is reserved for future processors  
Upper equals  
Final VID - 1.25 m * Icc  
450mV  
Lower equals  
Start VID - 1.25 m * Icc - 30mV  
low VID to high VID  
Vcc transition  
50µs maximum settling  
from registering final VID  
Maximum  
Vcc  
high VID to low VID  
Vcc transition  
settling  
50µs maximum settling  
from registering final VID  
Upper equals  
Final VID - 1.25 m * Icc  
450mV  
Lower equals  
Start VID - 1.25 m * Icc - 30mV  
The diagram assumes steady state, constant current during the dynamic VID  
transitions for ease of illustration; actual processor behavior allows for any dIcc/dt  
event during the transitions, depending on the code it is executing at that time  
The processor load may not be sufficient to absorb all of the energy from the output  
capacitors on the baseboard, when VIDs change to a lower output voltage. The VRM/  
EVRD design should ensure that any energy transfer from the capacitors does not  
impair the operation of the VRM/EVRD, the AC-DC supply, or any other parts of the  
system.  
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2.9  
Overshoot at Turn-On or Turn-Off - REQUIRED  
The core VRM/EVRD output voltage should remain within the load-line regulation band  
for the VID setting, while the VRM/EVRD is turning on or turning off, with no over or  
undershoot out of regulation. No negative voltage below –100 mV may be present at  
the VRM/EVRD output during turn-on or turn-off.  
2.10  
Output Filter Capacitance - REQUIRED  
The output filter capacitance for the VRM/EVRD11.0 based designs will be located on  
the baseboard. The system design must ensure that the output voltage of the VRM/  
EVRD conforms to the load line of Figure 2-2 and with the baseboard and processor  
loads. Table 2-7 shows the number of decoupling caps recommended and other related  
specifications based on updated processor power requirements supported by VRM/  
EVRD 11.0.  
Table 2-6.  
Recommended Decoupling and Other Specifications for Supported  
(Highest SKU) Processors - Summary  
560µF  
Alum-  
Polymer  
Slew Rate  
(di/dt)  
A/µs  
100µF  
MLCC  
10µF  
MLCC  
22 µF  
MLCC  
Max Icc  
(A)  
Processor  
Itdc (A)  
Dual-Core Intel Xeon Processor-  
Based Server platform 8 layer (3-  
PWR 3-GND and 2 SIG)  
17  
15  
54  
1200  
130  
150  
150  
(0805)  
Dual-Core Intel Xeon Processor-  
Based Server platform with Intel  
5000 Chipsets 6 layer (2-PWR, 2-  
GND and 2-SIG), 1 oz Cu  
44  
(1206)  
1200  
130  
130  
Dual-Core Intel Xeon Processor-  
Based Server platform with Intel  
5000 Chipsets 8 layer (3-PWR, 3-  
GND and 2-SIG), 1 oz Cu  
13  
44  
(1206)  
1200  
150  
Dual-Core Intel Xeon 5000 Series  
processors with Intel 5400 Chipsets  
Platform 8-Layer CRB MB  
12  
18  
10  
58  
1000  
1000  
Dual-Core Intel Xeon 7000 Series  
processors with Intel 7300 Chipsets  
Platform 14-Layer CRB MB  
65  
130  
150  
Figure 2-7 through Figure 2-10 are recommended examples of baseboard decoupling  
solutions and processor loads. Dual-Core Intel Xeon Processor-Based Server decoupling  
®
®
applies to all Dual-Core Intel Xeon Processor-Based Server/Dual-Core Intel Xeon  
Processor-Based Server/Dual-Core Intel Xeon Processor-Based Workstation platforms.  
The number of capacitors needed could change based on updated processor power  
requirements. The values shown are for a four to five phase 200 kHz to 700 kHz  
switching 150 A IccMAX/130 A IccTDC voltage regulator design with an output inductor  
range of 0.15 µH to 0.5 µH. The type and number of bulk decoupling required is  
dependent on the voltage regulator design and it is highly recommended that the OEM  
work with the VR supplier for an optimal decoupling solution for their system and in  
accordance to the processor’s design requirements.  
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Figure 2-7. Six-layer Dual-Core Intel Xeon Processor-Based Server Platform VccP Power  
Delivery Impedance Model Path with 1206 Size Caps  
VR  
Motherboard  
Socket and Package  
15 X 560 uF  
20 pH  
0.33m  
35 X 10 uF  
MLCC 1206  
9 X 10 uF  
MLCC 1206  
58 pH  
0.51m  
Aluminum-Polymer  
8400 uF  
0.40m  
350 uF  
90 uF  
VR  
Sense  
Point  
PWL  
0.09m  
0.4m  
30A to 130A  
1000A/uS  
34 pH  
134 pH  
267 pH  
Figure 2-8. Eight-layer Dual-Core Intel Xeon Processor-Based Server Platform VccP  
Power Delivery Impedance Model Path with 1206 Size Caps  
VR  
Motherboard  
Socket and Package  
20 pH  
0.33m  
35 X 10 uF  
MLCC 1206  
13 X 560 uF  
Aluminum-Polymer  
9 X 10 uF  
MLCC 1206  
54 pH  
0.37m  
7280 uF  
0.46m  
350 uF  
90 uF  
VR  
Sense  
Point  
PWL  
0.09m  
0.4m  
30A to 130A  
1000A/uS  
34 pH  
134 pH  
307 pH  
Figure 2-9. Eight-layer Dual-Core Intel Xeon Processor-Based Server Platform VccP  
Power Delivery Impedance Model Path with 0805 Size Caps  
VR  
Motherboard  
Socket and Package  
54 pH  
0.43m  
20 pH  
17 X 560 uF  
Aluminum-Polymer  
45 X 10 uF  
MLCC 0805  
9 X 10 uF  
MLCC 0805  
0.33m  
9520 uF  
0.41m  
450 uF  
90 uF  
VR  
Sense  
Point  
PWL  
0.22m  
1.1m  
30A to 130A  
1000A/uS  
25 pH  
122 pH  
235 pH  
The platform processor decoupling design incorporates fifteen 560 µF Aluminum-  
polymer bulk capacitors and forty four 10 µF 1206 package ceramic high-frequency  
capacitors per processor for a 6 layer board, thirteen 560 µF Aluminum-polymer bulk  
capacitors and forty four 10 µF 1206 package ceramic high-frequency capacitors per  
processor for a 8 layer board and seventeen 560 µF Aluminum-polymer bulk capacitors  
and fifty four 10 µF 0805 package ceramic high-frequency capacitors per processor for  
a 8 layer board (Table 2-8). At least nine of the 10 µF capacitors should be placed in the  
cavity of the processor socket. The remaining capacitors can be placed under the  
processor socket on the backside of the baseboard. The 560 µF capacitors should be  
placed along the sides of the processor socket, as close to the socket as the keep-out  
zones allow and on the south east side of the processor socket where the bulk of the  
power pins are located.  
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Note:  
The amount of bulk decoupling needed is dependent on the voltage regulator design.  
Some multiphase buck regulators may have a higher switching frequency that would  
require a different output decoupling solution to meet the processor load line  
requirements than described in this document.  
Table 2-7.  
Dual-Core Intel Xeon Processor-Based Server/Dual-Core Intel Xeon  
Processor-Based Server-VS/Dual-Core Intel Xeon Processor-Based  
Workstation Platform Processor Decoupling Capacitor Recommendations  
6 layers, (2 power, 2 ground, 2 signal), 1 oz Cu  
Temperature  
Coefficient  
ESR  
(mΩ)  
ESL  
(nH)  
Quantity  
Value  
Tolerance  
Notes  
15  
35  
9
560 µF Al-Polymer  
10 µF 1206 Ceramic  
10 µF 1206 Ceramic  
±20%  
±20%  
±20%  
NA  
7
3
3
4
X5R or X6S  
X6S  
1.2  
1.2  
1
8 layers, (3 power, 3 ground, 2 signal), 1 oz Cu  
Temperature  
Coefficient  
ESR  
(mΩ)  
ESL  
(nH)  
Quantity  
Value  
Tolerance  
Notes  
13  
35  
9
560 µF Al-Polymer  
10 µF 1206 Ceramic  
10 µF 1206 Ceramic  
±20%  
±20%  
±20%  
NA  
7
3
3
4
X5R or X6S  
X6S  
1.2  
1.2  
1
8 layers, (3 power, 3 ground, 2 signal), 1 oz Cu  
Temperature  
Coefficient  
ESR  
(mΩ)  
ESL  
(nH)  
Quantity  
Value  
Tolerance  
Notes  
17  
45  
9
560 µF Al-Polymer  
10 µF 0805 Ceramic  
10 µF 0805 Ceramic  
±20%  
±20%  
±20%  
NA  
7
4
X5R or X6S  
X6S  
10  
10  
1.1  
1.1  
1
Notes:  
1. Only the decoupling caps inside the socket cavity need to have the temperature coefficient of “X6S.  
Table 2-9.  
Dual-Core Intel Xeon 7000 Series with Intel 7300 Chipsets Platform Processor  
Decoupling Capacitor Recommendations  
ESR  
(mΩ)  
ESL  
(nH)  
Quantity  
Value / Description  
Notes  
18  
65  
560µF/2.5V/20%/ Oscon  
22µF/6.3V/20%/ X5R /1206 MLCC  
6.3  
4
3.2  
0.52  
Notes: Dual-Core Intel Xeon 7000 Series processors with Intel 7300 Chipsets baseboard has 14-layers. Refer  
to the latest Dual-Core Intel Xeon 7000 Series processors with Intel 7300 Chipsets Platform Design  
Guide for baseboard stack-up details.  
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Figure 2-10. Dual-Core Intel Xeon 5000 Series with Intel 5400 Chipsets Platform VccP  
Power Delivery Impedance Model Path - Example  
Motherboard  
Socket & Package  
VR  
HF Caps in  
socket cavity  
9x 10µF  
HF Caps  
49x 10µF  
MLCC 1206  
Low Fr Caps  
12x 560µF  
Oscon  
Mid Fr Caps  
10x 100µF  
Sense  
Point  
20 pH  
MLCC 1206  
MLCC 1210  
0.51 mO  
54 pH  
0.33 mO  
30A to  
130A  
90µF  
490µF  
6.72mF  
1mF  
1000A/us  
0.58 mO  
0.56 mO  
0.08 mO  
0.4 mO  
52 pH  
20 pH  
0.11 nH  
0.33 nH  
Table 2-10. Dual-Core Intel Xeon 5000 Series with Intel 5400 Chipsets Platform Processor  
Decoupling Capacitor Recommendations  
Temperature  
Coefficient  
ESR  
(mΩ)  
ESL  
(nH)  
Quantity  
Value  
Tolerance  
Notes  
12  
10  
58  
560 µF Al-Polymer  
100 µF 1210 MLCC  
10 µF 1206 MLCC  
±20%  
±10%  
±10%  
Oscon  
X6S  
7
4
5
4
0.52  
1
1
1
X5R or X6S  
1, 2  
Notes:  
1.  
Dual-Core Intel Xeon 5000 Series processors with Intel 5400 Chipsets platform has 8-layer stackup. Refer  
to the latest Dual-Core Intel Xeon 5000 Series processors with Intel 5400 Chipsets Platform Design Guide  
for baseboard stack-up details.  
2.  
9 of these HF caps are inside the processor socket cavity.  
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Output Voltage Requirements  
2.11  
Shut-Down Response - REQUIRED  
Once the VRM/EVRD is operating after power-up, if either the Output Enable signal is  
de-asserted or a specific VID off code is received, the VRM/EVRD must turn off its  
output (the output should go to high impedance) within 500 ms and latch off until  
power is cycled. If the extended VR 10 VID table is selected, the VRM/EVRD should turn  
off its output if VID [6:0] = XX11111. If the VR 11.0 VID table is selected, there are  
four VID off states; VID [6:0] = 0000000, 0000001, 1111110, or 1111111.  
§
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Control Signals  
3 Control Signals  
3.1  
Output Enable (OUTEN) - REQUIRED  
The VRM/EVRD must accept an input signal to enable its output voltage. When  
disabled, the regulator’s output should go to a high impedance state and should not  
sink or source current. When OUTEN is pulled low during the shutdown process, the  
VRM/EVRD must not exceed the previous voltage level regardless of the VID setting  
during the shutdown process. Once operating after power-up, it must respond to a  
deasserted OUTEN within 500 ms. The circuitry driving OUTEN is an open-collector/  
drain signal. It is EXPECTED that the pull-up resistor will be located on the baseboard  
and will not be integrated into the PWM controller chip or VRM.  
Table 3-1.  
OUTEN Specifications  
Symbol  
Parameter  
Min  
Max  
Units  
VIH  
VIL  
Input Voltage High  
Input Voltage Low  
0.8  
0
3.465  
0.4  
V
V
3.2  
Voltage Identification (VID [6:0]) - REQUIRED  
The VRM/EVRD must accept a 7-bit code, VID [6:0], from the processor to set the  
reference Vcc operating voltage. Two VID code standards are supported within the  
VRM/EVRD 11.0 specification. The first is an extended VR 10 table that is fully  
compliant to the VRM/EVRD 10.2 standard, but adds an additional bit for 6.25 mV VID  
resolution. (See Table 3-3) The second is a VR 11.0 standard defined in Table 3-4. The  
VID_Select pin, Section 3.4, will identify which table is to be used. Designers should  
note that although the VR 11.0 VID code is comprised of eight bits, VID 7 is a provision  
for future Itanium-based processors. The VID 7 pin should be connected to VSS, VO- or  
GND on the VRM module’s printed circuit board. The platforms targeted by this design  
guideline will only require VID [6:0].  
If an “OFF” VID code is received, such as when no processor is installed, the regulator  
must disable its output voltage. If this disable code appears during previously normal  
operation, the regulator shall turn off its output within 500 ms. The circuitry driving  
each VID [6:0] signal can be an open-collector/drain or a push-pull output type gate.  
When driven by an open-collector / drain, these VID signals need to be pulled-up to the  
processor’s VTT voltage. Consult the appropriate platform design guide for the  
recommended pull-up resistor value. A typical value used is 510 Ohms. When driven by  
a push-pull output gate, the pull-up resistors are optional. Consult the appropriate  
processor EMTS for driver definition. Pull-ups to 12 V or 5 V are not supported by the  
CPU package and therefore are not permitted. It is EXPECTED that the pull-up  
resistors will be located on the baseboard and will not be integrated into the PWM  
controller chip or VRM.  
Table 3-2.  
VID [6:0] Specifications  
Symbol  
Parameter  
Min  
Max  
Units  
Notes  
V
Input High Voltage  
Input Low Voltage  
0.8  
0
VTT max  
0.4  
V
V
1
1
IH  
V
IL  
Note: 1) Other platform components may use VID inputs and may require tighter limits.  
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Control Signals  
Table 3-3.  
Extended VR 10 Voltage Identification (VID) Table  
VID4  
VID3  
VID2  
VID1  
VID0  
VID5  
VID6 Voltage  
VID4  
VID3  
VID2  
VID1  
VID0  
VID5  
VID6 Voltage  
400 mV 200 mV 100 mV 50 mV 25 mV 12.5 mV 6.25 mV (V)  
400 mV 200 mV 100 mV 50 mV 25 mV 12.5 mV 6.25 mV (V)  
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1.6  
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1.2  
1.59375  
1.5875  
1.58125  
1.575  
1.56875  
1.5625  
1.55625  
1.55  
1.54375  
1.5375  
1.53125  
1.525  
1.51875  
1.5125  
1.50625  
1.5  
1.49375  
1.4875  
1.48125  
1.475  
1.46875  
1.4625  
1.45625  
1.45  
1.44375  
1.4375  
1.43125  
1.425  
1.41875  
1.4125  
1.40625  
1.4  
1.39375  
1.3875  
1.38125  
1.375  
1.36875  
1.3625  
1.35625  
1.35  
1.34375  
1.3375  
1.33125  
1.325  
1.31875  
1.3125  
1.30625  
1.3  
1.29375  
1.2875  
1.28125  
1.275  
1.26875  
1.2625  
1.25625  
1.25  
1.24375  
1.2375  
1.23125  
1.225  
1.21875  
1.2125  
1.20625  
1.19375  
1.1875  
1.18125  
1.175  
1.16875  
1.1625  
1.15625  
1.15  
1.14375  
1.1375  
1.13125  
1.125  
1.11875  
1.1125  
1.10625  
1.1  
1.09375  
OFF  
OFF  
OFF  
OFF  
1.0875  
1.08125  
1.075  
1.06875  
1.0625  
1.05625  
1.05  
1.04375  
1.0375  
1.03125  
1.025  
1.01875  
1.0125  
1.00625  
1
0.99375  
0.9875  
0.98125  
0.975  
0.96875  
0.9625  
0.95625  
0.95  
0.94375  
0.9375  
0.93125  
0.925  
0.91875  
0.9125  
0.90625  
0.9  
0.89375  
0.8875  
0.88125  
0.875  
0.86875  
0.8625  
0.85625  
0.85  
0.84375  
0.8375  
0.83125  
Note: An OFF VID code is equivalent to de-asserting the output enable input (Section 3.1).  
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Control Signals  
Table 3-4.  
VR 11.0 Voltage Identification (VID) Table  
Note: Only VID [6.0] are used for VRM/EVRD 11.0 platforms. The eighth VID bit is provisional for future  
Itanium-based platforms.  
3.3  
Differential Remote Sense (VO_SEN+/-) -  
REQUIRED  
The PWM controller shall include differential sense inputs to compensate for an output  
voltage offset of less than 300 mV in the power distribution path. This common mode  
voltage is expected to occur due to transient currents and parasitic inductances and is  
not expected to be caused by parasitic resistances.  
It’s recommended that the remote sense lines’ current draw will not push the actual  
Load Line outside of the Load Line limits shown in Table 2-3. As a practical guideline to  
minimizing offset errors, it is recommended that the combination of the sense resistor  
values and the remote sense current draw will result in the total DC voltage offset <=  
2 mV.  
Note:  
VCC_DIE_SENSE, VSS_DIE_SENSE, VCC_DIE_SENSE2 and VSS_DIE_SENSE2 of the processor pins  
are to be used as the VR sense input.  
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Control Signals  
Figure 3-1. Remote Sense Routing example.  
High Impedance Path  
1k 1%  
VCC_ DIE_ SENSE2  
LGA 771 Socket  
Pin AL8  
Pin AL7  
Pin AN3  
Pin AN4  
10 1%  
VSS_ DIE_ SENSE2  
VCC_ DIE_ SENSE  
VSS_ DIE_ SENSE  
10 1%  
10 1%  
10 1%  
In µP  
1 of 9  
10µF  
VCC/ VSS Feedback  
Cavity  
Inputs  
EVRD11.0 Controller or  
VRM 11.0 Connector  
High Impedance Path  
1k 1%  
Notes: For each processor, refer to the appropriate platform design guide (PDG) for the recommended VR’s  
remote sense routing.  
The sense lines should be routed based on the following guidelines:  
• Route differentially with a maximum of 5 mils separation.  
Traces should be at least 25 mils thick, but may be reduced when routed through  
the processor pin field.  
Traces should have the same length.  
Traces should not exceed 5 inches in length and should not violate pulse-width  
modulation (PWM) vendor length requirements.  
Traces should be routed at least 20 mils away from other signals.  
• Each sense line should include a 0 – 100 Ω, 5% series resistor that is placed close to  
the PWM or VRM connector in order to filter noise from the power planes. Designers  
should consult with their power delivery solution vendor to determine the  
appropriate resistor value.  
• Reference a solid ground plane.  
• Avoid switching layers.  
On a VRM, the positive sense line will be connected to VO_SEN+ and the negative  
sense line will be connected to VO_SEN–.  
The processor VCC_DIE_SENSE, VSS_DIE_SENSE, VCC_DIE_SENSE2 and VSS_DIE_SENSE2 pins  
should be connected to test points on the baseboard in order to probe the die voltage.  
These test points should be as close to the socket pins as possible.  
A high impedance path (100X) should be routed to the center of the processor socket  
and terminated to one of the nine 10 µF capacitors. This provision serves as a  
precautionary regulation point, in the event the EVRD/VRM is powered on and  
processor is installed.  
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Control Signals  
3.4  
Load Line Select (LL0, LL1, VID_Select) -  
REQUIRED  
The VID_Select, LL1 and LL0 control signal form a 3-bit load line selection and will used  
to configure the VRM/EVRD to supply the proper load line for the processors. These  
signals are programmed by the CPU package pin bonding. The VID_Select control  
signal will select the appropriate VR10 or VR11 VID table and remap the VID [6:0] pins  
to the appropriate DAC input. The signals are open-collector/drain or equivalent  
signals. Table 3-5 shows the VID_Select, LL1, and LL0 pins specification and Table 3-6  
shows equations in how to obtain V  
and V  
based on LL0, LL1, and VID_Select bit  
MAX  
MIN  
code. For VRMs a set of additional signals extent the usability of a modular solution,  
refer to Figure 6-1.  
It is EXPECTED that the pull-up resistors for LL0 and LL1 will be located on the  
baseboard and will not be integrated into the VRM. However, the pull-up resistor for  
VID_Select should be located on the VRM and to maintain backward compatibility to  
VRM 10.2 compliant platforms a pull-down resistor of 10 kΩ is also required. The pull-  
down resistor is required for VRMs only and not required for EVRDs. Typically, for EVRD  
converters, this signal will be pulled up to VTT (1.1 V/1.2 V) via a 4.7 kΩ resistor. As an  
option, 3.3 V with ± 5% regulation tolerance, may be used instead of VTT for VRM or  
EVRD converters. Pull-ups to 12 V or 5 V are not supported by the CPU package.  
The VR 10 and VR 11.0 VID pins do not have the same voltage weight. See Table 3-6  
for the VID bit mapping.  
Table 3-5.  
Table 3-6.  
LL0, LL1, VID_Select Specifications  
Symbol  
Parameter  
Output Low Current  
Min  
Max  
Units  
I
0
0.8  
0
4
mA  
V
OL  
V
Input Voltage High  
Input Voltage Low  
3.465  
0.4  
IH  
V
V
IL  
VID Bit Mapping  
VR 10.x  
-
VID 4  
400mV  
VID 6  
VID 3  
VID 2  
100mV  
VID 4  
VID 1  
50mV  
VID 3  
VID 0  
25mV  
VID 2  
VID 5  
VID 6  
6.25mV  
VID 0  
bit  
weight  
800mV  
VID 7  
200mV  
VID 5  
12.5mV  
VID 1  
VR 11.0  
§
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Control Signals  
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Input Voltage and Current  
4 Input Voltage and Current  
4.1  
Input Voltages - EXPECTED  
The power source for the VRM/EVRD is 12 V +5% / –8%. This voltage is supplied by a  
separate power supply. For input voltages outside the normal operating range, the  
VRM/EVRD should either operate properly or shut down.  
4.2  
Load Transient Effects on Input Current -  
EXPECTED  
The design of the VRM/EVRD, including the input power delivery filter, must ensure that  
the maximum slew rate of the input current does not exceed 0.5 A/µs, or as specified  
by the separate power supply.  
Note:  
In the case of a VRM design, the input power delivery filter may be located either on  
the VRM or on the baseboard. The decision for the placement of the filter will need to  
be coordinated between the baseboard and VRM designers.  
It is recommended that the bulk input decoupling (with optional series 0.1-1 µH  
inductor) be placed on the baseboard by the VRM input connector and high frequency  
decoupling on the VRM module. Expected baseboard decoupling should be between  
1000 µF to 2240 µF depending on VRM design and system power supply.  
§
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Input Voltage and Current  
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Processor Voltage Output Protection  
5 Processor Voltage Output  
Protection  
These are features built into the VRM/EVRD to prevent fire, smoke or damage to  
itself, the processor, or other system components.  
5.1  
5.2  
Over-Voltage Protection (OVP) - EXPECTED  
The OVP circuit monitors the processor core voltage (Vcc) for an over-voltage  
condition. If the output is more than 200 mV above the VID level, the VRM/EVRD shuts  
off the output.  
Over-Current Protection (OCP) - EXPECTED  
The core VRM/EVRD should be capable of withstanding a continuous, abnormally low  
resistance on the output without damage or over-stress to the unit. Output current  
under this condition will be limited to no more than 120% of the maximum peak rated  
output of the voltage regulator at thermal equilibrium under the specified ambient  
temperature and airflow.  
§
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Processor Voltage Output Protection  
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Output Indicators  
6 Output Indicators  
6.1  
Voltage Regulator Ready (VR_Ready) - REQUIRED  
The VRM/EVRD VR_Ready signal is an output signal that indicates the start-up  
sequence is complete and the output voltage has moved to the programmed VID value.  
This signal will be used for start-up sequencing for other voltage regulators, clocks, and  
microprocessor reset. This signal is not a representation of the accuracy of the DC  
output to its VID value.  
The platform VR_Ready signal(s) will be connected to logic to assert CPU or system  
PWRGD. The value of the resistor and the pull-up voltage will be determined by the  
circuitry on the baseboard that is receiving this signal. Typically a 1 kΩ pull to 3.3 V is  
used. This signal should not be de-asserted during dynamic VID operation. It should  
remain asserted during normal DC-DC operating conditions and only de-assert for fault  
shutdown conditions. It will be an open-collector/drain or equivalent signal. The pull-up  
resistor and voltage source will be located on the baseboard. Table 6-1 shows the  
VR_Ready pin specification.  
Table 6-1.  
VR_Ready Specifications  
Symbol  
Parameter  
Output Low Current  
Min  
Max  
Units  
I
1
0.8  
0
4
mA  
V
OL  
V
Output High Voltage  
Output Low Voltage  
3.465  
0.4  
OH  
V
V
OL  
6.2  
Voltage Regulator Hot (VR_hot#) - PROPOSED  
The VRM/EVRD VR_hot# signal is an output signal that is asserted low when a thermal  
event is detected in the converter. Assertion of this signal will be used by the system to  
minimize damage to the converter due to the thermal conditions. Table 6-2 shows the  
VR_hot# signal specification. This signal will be an open-collector/drain or equivalent  
signal and needs to be pulled up to an appropriate voltage through a pull-up resistor on  
the baseboard. A typical implementation would be a 50 Ω ±5% resistor pulled up to  
1.1 V/1.2 V. For platforms using a voltage higher than 1.1 V /1.2 V, a voltage level  
translation is required. Processors do not tolerate such voltage levels directly. Consult  
the appropriate PDG.  
Table 6-2.  
VR_hot# Specifications  
Symbol  
Parameter  
Output Low Current  
Min  
Max  
Units  
I
19.9  
0.8  
0
30  
3.465  
0.4  
mA  
V
OL  
V
Output High Voltage  
Output Low Voltage  
OH  
V
V
OL  
Each customer is responsible for identifying maximum temperature specifications for all  
components in the VRM/EVRD design and ensuring that these specifications are not  
violated while continuously drawing specified Icc (TDC) levels. In the occurrence of a  
thermal event, a thermal sense circuit may assert the processor’s FORCEPR# signal  
immediately prior to exceeding maximum VRM, baseboard, and/or component thermal  
ratings to prevent heat damage. The assertion may be made through direct connection  
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Output Indicators  
to the FORCEPR# pin or through system management logic. Assertion of this signal will  
lower processor power consumption and reduce current draw through the voltage  
regulator, resulting in lower component temperatures. Sustained assertion of the  
FORCEPR# pin will cause noticeable platform performance degradation and should not  
occur when drawing less than the specified thermal design current for a properly  
designed system.  
It is recommended that hysteresis be designed into the thermal sense circuit to prevent  
a scenario in which the VR_hot# signal is rapidly being asserted and de-asserted.  
6.3  
Load Indicator Output (Load_Current) -  
PROPOSED  
The VRM/EVRD may have an output with a voltage (Load_Current) level that varies  
linearly with the VRM/EVRD output current. The PWM controller supplier may specify a  
voltage-current relationship consistent with the controller’s current sensing method.  
Baseboard designers may route this output to a test point for system validation.  
6.4  
VRM Present (VRM_pres#) - EXPECTED  
The VRM should have the VRM_pres# signal. This signal is an output signal used to  
indicate to the system that a VRM 10.x compatible module is plugged into the socket.  
VRM_pres# is an open-collector/drain or equivalent signal. Table 6-3 shows the  
VRM_pres# pin specification. It is EXPECTED that the pull-up resistor will be located  
on the baseboard and will not be integrated into the VRM.  
Table 6-3.  
VRM_pres# Specifications  
Symbol  
Parameter  
Output Low Current  
Min  
Max  
Units  
I
0
0.8  
0
4
mA  
V
OL  
V
Output High Voltage  
Output Low Voltage  
5.5  
0.4  
OH  
V
V
OL  
6.5  
VR_Identification (VR_ID#) - EXPECTED  
The VRM should have the VR_ID# signal. This signal is an output signal used to  
indicate to the system that a VR11-compatible VRM is plugged into the socket.  
VR_ID# is an open-collector/drain or equivalent signal. Table 6-4 shows the VR_ID#  
pin specification. It is EXPECTED that the pull-up resistor will be located on the  
baseboard and will not be integrated into the VRM.  
The VR_ID# signal combined with the VRM_pres# signal forms a two-bit VRM  
identification code to indicate the type of module installed in a system. Figure 6-1  
defines the two signal decode.  
Table 6-4.  
VRM_ID# Specifications  
Symbol  
Parameter  
Output Low Current  
Min  
Max  
Units  
I
0
0.8  
0
4
mA  
V
OL  
V
Output High Voltage  
Output Low Voltage  
5.5  
0.4  
OH  
V
V
OL  
38  
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Figure 6-1. VRM 11.0 and Platform Present Detection  
VRID#  
VRM_Pres#  
(MB Pull-up,  
VRM Pull-  
DWN)  
VID_SELECT LL1 (MB LL0 (MB Outcome VRD11.0 Module  
Outcome in VRM10.2 Platform  
(VRM11.0 Backward Compatible;  
VR10.2 platform doesn't have  
VR_ID# and VID_Select)  
(MB  
PullUP,  
VRM Pull  
DWN)  
0
Outcome in VRM11.0  
Platform  
(VRM Pulldwn, PullUP,  
Pull UP,  
(130Atdc, 150Apk, VID11.0  
Platform  
pullup)  
CPU Pull CPU Pull and VID10.2 compat, 30mV  
DWN)  
DWN)  
tol)  
0
0
0
0
0
0
0
1
Possible, ref Table 2-3  
Possible, ref Table 2-3  
Possible, ref Table 2-3  
Possible, ref Table 2-3  
Reserved  
Reserved  
0
Dual-Core Intel® Xeon® 7100 series  
processors (1.25mOHM / VID10.2)  
Reserved  
Not possible, no pullup for VID_Select  
Not possible, no pullup for VID_Select  
Not possible, no pullup for VID_Select  
Not possible, no pullup for VID_Select  
0
0
0
1
0
Possible, ref Table 2-3  
Possible, ref Table 2-3  
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
Possible, ref Table 2-3  
Possible, ref Table 2-3  
Possible, ref Table 2-3  
Possible, ref Table 2-3  
Possible, ref Table 2-3  
Possible, ref Table 2-3  
Possible, ref Table 2-3  
Possible, ref Table 2-3  
Possible, ref Table 2-3  
Possible, ref Table 2-3  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
N/A  
No Turn On VRM 10.2 present Not possible, no pullup for VR_ID#  
No Turn On VRM 10.2 present Not possible, no pullup for VR_ID#  
No Turn On VRM 10.2 present Not possible, no pullup for VR_ID#  
No Turn On VRM 10.2 present Not possible, no pullup for VR_ID#  
No Turn On VRM 10.2 present Not possible, no pullup for VR_ID#  
No Turn On VRM 10.2 present Not possible, no pullup for VR_ID#  
No Turn On VRM 10.2 present Not possible, no pullup for VR_ID#  
No Turn On VRM 10.2 present Not possible, no pullup for VR_ID#  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
Not possible, no pullup for VR_ID#  
Not possible, no pullup for VR_ID#  
Not possible, no pullup for VR_ID#  
Not possible, no pullup for VR_ID#  
Not possible, no pullup for VR_ID#  
Not possible, no pullup for VR_ID#  
Not possible, no pullup for VR_ID#  
Not possible, no pullup for VR_ID#  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
no module present  
§
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VRM – Mechanical Guidelines  
7 VRM – Mechanical Guidelines  
7.1  
VRM Connector - EXPECTED  
The part number and vendor name for VRM 11.0 connectors that can be found in  
Table 7-1. The VRM reference in Section 7.2, Section 7.3 and Section 7.4, is based on  
the Tyco*/Elcon* interface with the system board is a 27-pin pair edge connector. The  
connector uses latches to hold the VRM in place. The connector will be rated to handle  
a continuous load current of 130 A.  
Table 7-1.  
VRM 11.0 Connector Part Number and Vendor Name  
Connector  
Vendor Part Number  
Notes  
1651929-1 (Solder Tail)  
1766336-1 (Surface Mount)  
1766436-1 (Press-Fit)  
Tyco / Elcon  
1
Molex iCool* VRM 24 signal 70 power pins  
87787-1012 (Vertical, TH)  
87786-1011 (Vertical, SM)  
Molex  
1, 2  
87818-1011 (Right Angle, TH)  
Notes:  
1.  
These vendors are listed by Intel as a convenience to Intel's general customer base, but Intel does not  
make any representations or warranties whatsoever regarding quality, reliability, functionality, or  
compatibility of these devices. This list and/or these devices may be subject to change without notice.  
An alternative connector has been identified by Molex for VRMs. This alternative provides many optional  
connector variants already in production in both vertical and horizontal (right angle) implementation.  
Contact your Molex representative for pin assignment, mechanical form factor details and performance  
characteristic data.  
2.  
7.2  
VRM (Tyco/Elcon) Connector Keying  
7.2.1  
Connector Keying  
• Single notch between pins 3 and 4 (51 and 52 opposite side).  
• Single notch between pins 12 and 13 (42 and 43 opposite side).  
• Single notch between pins 21 and 22 (33 and 34 opposite side).  
7.2.2  
Connector Pin 1 Orientation  
Referencing Figure 7-1, Outline Drawing, Far Side (FS) pins sequence 1 through 27, left  
to right. Near Side (NS) pins sequence 54 through 28. Pin 1 and 54 are opposite one  
another.  
7.3  
Pin Descriptions and Assignments  
Table 7-2 shows the VRM11.0 connector pin description. Pin assignments are shown in  
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VRM – Mechanical Guidelines  
Table 7-2.  
VRM 11.0 Connector Pin Descriptions  
Name  
Type  
Output  
Description  
Load_Current  
OUTEN  
Analog signal representing the output load current  
Output enable  
Input  
VR_Ready  
Output  
Output signal indicating that the start-up sequence is complete and the  
output voltage has moved to the programmed VID value.  
1
VID [6:0]  
Input  
Voltage ID pins used to specify the VRM output voltage  
VRM Input Voltage  
VIN+  
VIN−  
VO+  
VO−  
Power  
Ground  
Power  
Ground  
Input  
VRM Input Ground  
VRM Output Voltage  
VRM Output Ground  
VO_SEN+  
VO_SEN–  
Output voltage sense pins  
VR_hot#  
Output  
Output  
Indicates to the system that a thermal event has been detected in the VR  
VRM_pres#  
Indicates to the system that a VR10-compatible VRM is plugged into the  
socket  
VR_ID#  
Output  
Indicates to the system that a VR11-compatible VRM is plugged into the  
socket  
LL0, LL1  
Input  
Input  
Used to configure VR load line value  
VID_Select  
Used to select between extended VR10 and VR11 VID tables  
Note: VID7 bit is not routed from the PWM control IC to the VRM connector; VID7is to be held Low on the VRM  
board.  
42  
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VRM – Mechanical Guidelines  
Figure 7-1. VRM 11.0 Pin Assignments  
1
VIN−  
54  
53  
52  
51  
50  
49  
48  
47  
46  
45  
44  
43  
42  
41  
40  
39  
38  
37  
36  
35  
34  
33  
32  
31  
30  
29  
28  
VIN+  
VIN+  
VIN+  
VID3  
VID1  
VID5  
VO_SEN−  
VR_hot#  
LL0  
2
VIN−  
3
VIN−  
KEY  
KEY  
KEY  
KEY  
KEY  
KEY  
4
VID4  
5
VID2  
6
VID0  
7
VO_SEN+  
VR_Ready  
OUTEN  
Load_Current  
VID6  
8
9
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
21  
22  
23  
24  
25  
26  
27  
LL1  
VID_Select  
VR_ID#  
VO+  
VRM_pres#  
VO+  
VO+  
VO+  
VO+  
VO+  
VO−  
VO−  
VO−  
VO−  
VO−  
VO−  
VO+  
VO+  
VO+  
VO+  
VO+  
VO+  
VO−  
VO−  
VO−  
VO−  
VO−  
VO−  
VO+  
VO+  
VO+  
VO+  
VO+  
VO+  
7.4  
Mechanical Dimensions - PROPOSED  
The mechanical dimensions for the VRM 11.0 module and connector are shown in  
7.4.1  
Gold Finger Specification  
The VRM board must contain gold lands (fingers) for interfacing with the VRM  
connector that is 1.50 mm ±0.2 mm [0.059” ±0.008”] wide by 6.00 mm [0.236”]  
minimum long and spaced 2.50 mm [0.098”] apart. Traces from the lands to the power  
plane should be a minimum of 0.89 mm [0.035”] wide and of a minimal length.  
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VRM – Mechanical Guidelines  
Figure 7-1. VRM 11.0 Module and Connector  
96.52mm (3.80") MAX  
51.84mm  
(2.04”)  
59.3mm  
(2.33")  
Ref.  
2X R2.00mm (R0.08")  
65.34mm  
(2.57")  
MAX  
Component  
Keepout  
66.34mm  
(2.612")  
MAX  
1.70mm  
(0.067")  
View A  
7.87mm (0.310")  
13.50mm  
(0.531")  
15.50mm  
(0.610")  
20.0mm  
(0.79")  
View B  
12.0mm  
7.0mm  
(0.47")  
3.00mm  
(0.118")  
(0.276")  
22.97mm  
(0.904")  
28.9mm  
(1.138")  
22.88mm  
(0.901")  
10.16mm  
(0.4")  
MAX  
13.18mm  
(0.519")  
View A  
93.34mm (3.675") MAX  
1.50+/- 0.2mm  
PIN 54  
(0.059 +/- 0.008")  
NEAR SIDE Components  
FAR SIDE Components  
14.27mm  
(0.562")  
MAX  
6.00mm  
(0.236")  
PIN 1  
OPEN Latches 114.98mm (4.527") MAX  
CLOSED Latches 102.5mm (4.035") MAX  
1.80mm  
(0.071")  
Connector Length 97.54mm (3.840") MAX  
66.77mm (2.629")  
View B  
1.00+0/-0.13mm  
(0.039+0/-0.005")  
36.07mm (1.420")  
10.53mm(0.415")  
R 0.65mm  
(R0.026")  
9.70mm (0.382")  
PIN 54  
PIN 28  
9.03mm  
(0.356")  
MAX  
3.33mm  
(0.131")  
PCB  
30  
Edge Card  
Contacts  
4.05mm  
(0.159")  
0.50mm  
(.020")  
PIN 1  
5.08mm  
(0.200")  
8x2.50mm  
(0.098")  
12x2.50mm 8.04mm  
hole diameter  
54x1.02+/-0.08mm  
(.040+/-.003")  
(0.098")  
(0.316")  
1.57mm +/- 0.20  
(.062" +/-.008)  
PCB Footprint  
§
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Environmental Conditions  
8 Environmental Conditions  
The VRM/EVRD design, including materials, should meet the environmental  
requirements specified below.  
8.1  
Operating Temperature - PROPOSED  
The VRM/EVRD shall meet all electrical requirements when operated at the Thermal  
Design Current (Icc  
) over an ambient temperature range of 0ºC to +45ºC with a  
TDC  
minimum airflow of 400 LFM (2 m/s). The volumetric airflow (Q) can be measured  
through a wind tunnel. For testing, the baseboard should be mounted in a duct. (A VRM  
should be mounted on a PCB, and then mounted in a duct.) The recommended duct  
cross-section, assuming the PCB is horizontal and flush with the bottom of the duct, is  
as follows:  
• Y direction duct width (perpendicular to flow, horizontal) = 0.3 m  
• Z direction duct height (perpendicular to flow, vertical) = 0.15 m  
• Minimum X direction duct length in front of VRM = 6 hydraulic diameters = 1.2 m  
• Minimum X direction duct length behind VRM = 2 hydraulic diameters = 0.4 m  
• Velocity (v) is calculated from the volumetric flow and cross-sectional area at the  
inlet as:  
2
• v = Q/(0.3 x 0.15)m Operating conditions shall be considered to include 10 cycles  
between min and max temperature at a rate of 10ºC/hour and a dwell time of 30  
minutes at extremes. Temperature and airflow measurements should be made in  
close proximity to the VRM.  
8.2  
VRM Board Temperature - REQUIRED  
To maintain the connector within its operating temperature range, the VRM board  
temperature, at the connector interface, shall not exceed a temperature equal to 90ºC.  
At no time during the operation is the board permitted to exceed 90ºC within a distance  
of 2.54 mm [0.100”] from the top of connector (0.4 in. from board edge). In order not  
to exceed 90ºC, it is recommended that the board be constructed from 2-ounce copper  
cladding. Temperature and airflow measurements should be made in close proximity to  
the VRM.  
8.3  
8.4  
Non-Operating Temperature - PROPOSED  
The VRM/EVRD shall not be damaged when exposed to temperatures between –40ºC  
and +70ºC. These shall be considered to include 50 cycles of minimum to maximum  
temperatures at 20ºC/hour with a dwell time of 20 minutes at the extremes.  
Humidity - PROPOSED  
85% relative – operating  
95% relative – non-operating  
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Environmental Conditions  
8.5  
8.6  
Altitude - PROPOSED  
3.05 km [10 k feet] – operating  
15.24 km [50 k feet] – non-operating  
Electrostatic Discharge - PROPOSED  
Testing shall be in accordance with IEC 61000-4-2.  
Operating – 15 kV initialization level. The direct ESD event shall cause no out-of-  
regulation conditions – including overshoot, undershoot and nuisance trips of over-  
voltage protection, over-current protection or remote shutdown circuitry.  
Non-operating –25 kV initialization level. The direct ESD event shall not cause damage  
to the VRM circuitry.  
8.7  
Shock and Vibration - PROPOSED  
The shock and vibration tests should be applied at the baseboard level. The VRM/EVRD  
should not be damaged and the interconnect integrity not compromised during:  
• A shock of 50 g (± 10%) with velocity change of 170 inches/sec (± 10%) applied  
three times in each of the orthogonal axes.  
• Vibration of 0.01 g² per Hz at 5 Hz, sloping to 0.02 g² per Hz at 20 Hz and  
maintaining 0.02 g² per Hz from 20 Hz to 500 Hz for 10 minute per axis applied in  
each of the orthogonal axes.  
8.8  
8.9  
Electromagnetic Compatibility - PROPOSED  
Design, including materials, should be consistent with the manufacture of units that  
comply with the limits of FCC Class B and CISPR22 Class B for radiated emissions.  
Reliability - PROPOSED  
Design, including materials, should be consistent with the manufacture of units with a  
Mean Time Between Failure (MTBF) of 500,000 hours of continuous operation at 55ºC,  
maximum-outputs load, and worst-case line, while meeting specified requirements.  
MTBF should be calculated in accordance with MIL-STD-217F or Bellcore.  
8.10  
Safety - PROPOSED  
The voltage regulator is to be UL Recognized to standard UL1950 3rd Ed., including  
requirements of IEC950 and EN 60950. Plastic parts and printed wiring board are to be  
UL Recognized with 94V-0-flame class.  
§
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Manufacturing Considerations  
9 Manufacturing Considerations  
9.1  
Lead Free (Pb Free)  
The use of lead in electronic products is an increasingly visible environmental and  
political concern. The drivers for the reduction or elimination of lead in electronic  
products include:  
• Customer desire for environmentally friendly (‘green’) products.  
• Manufacturer desire to be environmentally friendly, and be perceived as such.  
• Government initiatives regarding recycling of electronic products.  
• Planned and potential legislation.  
The most notable legislation is the European Union (EU) Restriction on Hazardous  
Materials directive, also known as RoHS. The commission directive may be found at the  
following URL:  
l_03720030213en00190023.pdf  
European Union “Member States shall ensure that, from 1 July 2006, new electrical and  
electronic equipment put on the market does not contain lead...Each EU country will  
implement this law and establish penalties and fines for non-compliance. The RoHS  
directive includes certain exemptions:  
• Lead in high melting temperature type solders (i.e. tin-lead solder alloys containing  
more than 85% lead).  
• Lead in solders for servers, storage and storage array systems (exemption granted  
until 2010).  
• Lead in solders for network infrastructure equipment for switching, signaling,  
transmission as well as network management for telecommunication.  
• Lead in electronic ceramic parts (e.g. piezoelectronic devices).  
For the latest information on RoHS please refer to the following URL:  
Intel recommends that you consider Pb Free manufacturing processes and components  
for the module and module connector.  
§
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Z(f) Constant Output Impedance Design  
A Z(f) Constant Output  
Impedance Design  
A.1  
Introduction - PROPOSED  
The VRM/EVRD performance specification is based on the concept of output impedance,  
commonly known as the load line. The impedance is determined by the Pulse Width  
Modulator (PWM) controller’s Adaptive Voltage Positioning (AVP), up to the loop  
bandwidth of the regulator and the impedance of the output filter and socket beyond  
the loop bandwidth.  
®
Figure A-1. Typical Intel Microprocessor Voltage Regulator Validation Setup  
ZPCB1  
ZPCB2  
ZPskt  
Vin  
VTT  
ZBulk  
ZHF1  
ZHF2  
PWM  
VFB  
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Z(f) Constant Output Impedance Design  
Figure A-2. Z(f) Network Plot with 1.25 mΩ Load Line  
The impedance plot Z(f) shown in Figure A-2 can be divided up into three major areas  
of interest.  
• Low frequency, Zero Hz (DC) to the VR loop bandwidth. This is set by AVP and loop  
compensation of the VR controller or PWM control IC.  
• Middle frequency, VR loop bandwidth to socket inductance rise - This is set by the  
bulk capacitors, MLCC capacitors and PCB layout parasitic elements.  
• High frequency, controlled by socket inductance and the CPU package design.  
The VRM/EVRD designer has control of the low and mid frequency impedance design.  
By ensuring these areas meet the load line target impedance in Section 2.2, the system  
design will work properly with future CPU package designs.  
Figure A-2 shows the impedance vs. frequency network the system in Figure 2-1. This  
example consists of 17 560 μF with an ESR of 7 mΩ and ESL of 4 nH per bulk  
st  
capacitors, 1 PCB impedance of 1.0 μΩ and 0.05 pH between the bulk and 45 10 μF  
nd  
0805 MLCC, with ESR is 10 mΩ and ESL of 1.1 nH, 2 PCB impedance of 1.0 μΩ and  
0.05 pH between the 45 10 μF and the 9 10 μF 0805 MLCC in the socket cavity with ESR  
is 10 mΩ and ESL of 1.1 nH, and the LGA771 socket impedance of 330 μΩ and 20 pH.  
The resonant point seen at 400 kHz is due to the mis-match between the bulk  
capacitors and the MLCC cavity capacitors. Increasing the capacitance values will drop  
the magnitude and shift the to a lower resonance frequency. For example, if the 10 μF  
capacitors are increased to 22 μF, the resonant peak drops in magnitude to 1.0 mΩ and  
at a frequency of 200 kHz. The resonant peak could also be reduced by reducing the  
ESL of the bulk capacitors by changing capacitor technology or by adding more bulk  
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Z(f) Constant Output Impedance Design  
capacitors in parallel. The effect of the mid frequency resonant point must be  
investigated and validated with Vdroop testing to ensure any current load transient  
pattern, does not violate the V load line.  
min  
By defining the output impedance load line over a frequency range, the voltage  
regulation or voltage droop is defined at any current level as the output current  
multiplied by the impedance value. Currently, output impedance is validated in the time  
domain by measuring the voltage response to a known current step. In Figure A-1, the  
VTT tool replaces the CPU and the package for platform validation purposes. Typical  
measured voltage and currents are depicted in Figure A-3. The transient load line is  
defined as the voltage droop magnitude during the current rise time divided by the  
current step. The static load line is defined as the voltage level magnitude, after  
settling, divided by the current step. It is desired to have both the transient and static  
load line equal.  
Figure A-3. Time Domain Response of a Microprocessor Voltage Regulator  
The static and transient load line measurements, measure the quality of different parts  
of the voltage regulator design. The transient load line is governed by the parasitic  
impedances in the output filter board layout, decoupling capacitors, and power  
distribution network. The static load line is governed by the PWM controller's AVP  
accuracy. The time domain Vdroop testing method gives pass, fail data on meeting the  
target specification, but gives little insight as to how to improve the voltage regulator's  
response. It can be difficult to determine if you need more bulk capacitance, more high  
frequency MLCC capacitance or higher loop bandwidth from the time domain Vdroop  
waveforms. By measuring the impedance, Z(f) of the voltage regulator, these trade-  
offs and optimizations can be made.  
The impedance can be measured with a network analyzer, but the network analyzer can  
only measure the passive filter components and will not show the effects of the VR loop  
bandwidth and AVP. Also MLCC capacitors impedance varies with DC bias and AC ripple  
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Z(f) Constant Output Impedance Design  
frequency applied by the application. Hence a better method is needed to extract the  
impedance profile with the VR operating. The following sections introduce the theory  
behind using a VTT tool to create an impedance profile for the VR system.  
A.2  
Voltage Transient Tool (VTT) Z(f) Theory  
The following expression is the definition of impedance as a function of frequency  
looking back from the VTT tool into the filter network and VRM.  
FFT(V (t))  
Z( f ) =  
FFT(I(t))  
The representation of the corresponding Fourier spectra of the voltage and current  
responses are shown in Figure A-2. The first harmonic values from the Fast Fourier  
Transform (FFT) are used in the calculation of Z(f). The ratio of the two, yields the  
impedance at a given frequency, f. By sweeping the VTT generated load transient  
repetition rate, I(t), over the desired region of interest, additional points are estimated  
on the impedance profile to obtain a near continuous impedance spectrum plot.  
In the VTT tool, the die voltage, V(t), is brought out through a pair of non-current  
carrying remote sense pins, tied to the Vcc and Vss power plane and measured on the  
VTT tool substrate. The current, I(t), is a differential voltage measured across the  
current shunt resistors in the VTT tool. The oscilloscope's math function is used to  
convert the time domain voltage droop and current measurements into their  
corresponding frequency domain spectrum. Since the FFT of the actual response  
waveforms are calculated, perfect square waves of current are not needed as a  
stimulus. The accuracy and frequency response of this method is limited to the current  
shunt resistor's accuracy and the shunt's parasitic inductance. Parasitic inductance in  
the current shunt resistors will over estimate the actual current and hence the method  
will under estimate the impedance at frequencies where the inductive voltage drop  
dominates the resistive voltage drop. The 50 pH of parasitic inductance in the VTT  
causes an over estimation of current for frequencies over 1 MHz and an under  
estimation of impedance. This can be corrected by post processing of the data and  
removing the inductive voltage spike.  
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Z(f) Constant Output Impedance Design  
Figure A-4. Time Domain Responses and Corresponding Fourier Spectra  
of Voltage, Current and Impedance  
A.3  
VTT Z(f) Measurement Method  
An electronic load that has the capability to change the repetition rate up to 3 MHz of  
the load step is needed. The Intel LGA771/775V2 VTT by Cascade Systems Design, will  
meet this requirement. By monitoring the VTT current and voltage waveforms with an  
oscilloscope capable of executing an FFT on these waveforms, the platform impedance  
is found. A complete impedance profile is then generated by sweeping the input  
waveform frequency across the range of interest. In order to automate the data  
collection process, Intel has modified the VTT control software and a GPIB controlled  
oscilloscope is used along with software supplied with the VTT.  
These utilities allow the user to automatically display and collect the magnitude and  
phase of the motherboard impedance in a Microsoft Excel* compatible data file. The  
total time it takes to extract the impedance profile using this method is about 1-2  
minutes. This technique is very useful in investigating and assuring MB performance  
based on its stack up.  
For more information on the measurement method and theory, see the paper  
Microprocessor Platform Impedance Characterization using VTT Tools by K. Aygun, S.  
Chickamenahalli, K. Eilert, M. Hill, K. Radhakrishnan and E. Stanford published at the  
IEEE Applied Power Electronics Conference, 2005.  
A.4  
Results  
As an example, Figure A-5 shows the test platform with 10 560 μF Al-Poly bulk  
capacitors and 10 10 μF and 8 22 μF high frequency MLCC capacitors in the socket  
cavity. Figure A-6 is the measured impedance profile of the board shown in Figure A-5  
as capacitors are removed. The VID setting for this measurement was 1.35 V and load  
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Z(f) Constant Output Impedance Design  
current was 40 A. The waveforms show the effect of capacitor depopulation on the  
impedance profile above 1 MHz as pairs of high frequency MLCC capacitors are  
removed (banks 1-9) per the bank designations depicted in Figure A-7.  
Simulation comparisons are made in Figure A-8 for the two extreme cases of the  
decoupling conditions of Figure A-7, with all MLCC plus two Al-Poly bulk capacitors in  
place and all cavity MLCCs plus two Al-Poly bulk capacitors removed. Simulation depicts  
a 6-layer distributed motherboard model. The VR model has a Type III feedback  
compensated switching VR (swvr) and an average model (avgvr). It can be observed  
from Figure A-8 that the switching model measurements agrees better beyond the VR  
bandwidth (40 kHz) than the average model, while the average VR model performance  
agrees with the overall trend. Slightly lower average model impedances are also  
observed and other disagreements are attributed to imperfect assumptions about the  
parasitics of the devices and specific adaptive voltage implementation in the VR  
models.  
Figure A-5. Photo of Motherboard Analyzed Showing High Frequency  
MLCC Capacitors In the Socket Cavity and Bulk Capacitors  
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Z(f) Constant Output Impedance Design  
Figure A-6. Measured Platform Impedance Profile Showing Change  
in Impedance as Capacitors Are Removed  
Magnitude of impedance profile  
10  
all caps installed  
1. 2x 10uF removed  
2. 2x 10uF removed  
9
3. 2x 10uF removed  
4. 2x 22uF removed  
8
5. 10, 22 uF removed  
6. 2x 22uF removed  
7
7. 10, 22uF removed  
8. 2x 10uF removed  
6
9. 2x 22uF removed  
MLCC + 1 Bulk removed  
5
MLCC +2 Bulk removed  
4
3
2
1
0
0.001  
0.01  
0.1  
1
10  
100  
frequency (MHz)  
Figure A-7. Designations of MLCC Cavity Capacitor Banks  
9
5
4 6  
1 2  
7 3  
8
10uF  
22uF  
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Z(f) Constant Output Impedance Design  
Figure A-8. Simulated and Measured Waveforms of Platform Impedance Profile  
measured vs simulated results  
10  
9
8
7
6
5
4
3
2
1
0
meas:allcaps  
meas:bank1-9+2oscons  
sim:swvr-allcaps  
sim:avgvr-allcaps  
sim:swvr-bank1-9+2osc  
sim:avgvr-bank1-9+2osc  
10-3  
10-2  
10-1  
frequency(MHz)  
100  
101  
A.5  
Output Decoupling Design Procedure  
1. Select type and number of bulk capacitors. Normally the equivalent ESR needs to  
be approximately ½ the load line target impedance. For a 1.25 mΩ load line, the  
equivalent ESR should be less than 0.625 mΩ. The reason for selecting the number  
of bulk capacitors to yield an equivalent ESR to be ½ the target impedance is to  
compensate for the parasitic resistance of the PCB layout plane shapes and for  
aging of the capacitors. This is a starting point for the design. The final number of  
bulk capacitors will be determined by transient droop testing and Z(f)  
measurements.  
2. The type and number of MLCC capacitors in the socket cavity is specified in the  
Section 2.10. These are required to meet both power delivery impedance and  
signal integrity issues.  
3. Design the PWM loop bandwidth compensation. The ideal loop BW is set at the  
frequency where the bulk capacitor impedance meets the target impedance curve.  
In Figure A-2, it is approximately 30 kHz. Small increases in the loop bandwidth will  
not improve system performance until the bandwidth is moved to where the MLCC  
impedance meets the target impedance at ~ 700 kHz which is impractical.  
Consult the PWM chip manufacturer's data sheets and application notes on calculating  
the PWM loop compensation and AVP programming values.  
§
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