Fujitsu Switch MB3788 User Manual

FUJITSU SEMICONDUCTOR  
DATA SHEET  
DS04-27209-3E  
ASSP  
SWITCHING REGULATOR  
CONTROLLER  
MB3788  
DESCRIPTION  
The MB3788 is a dual-channel PWM-type switching regulator controller; it incorporates a reference voltage.  
The MB3788 has a PWM circuit and an output circuit as well as a reference voltage power supply with a voltage  
accuracy of ±1%. The maximum operating frequency is 1 MHz. It is designed for a voltage-drop output switching  
regulator suitable for a logic power supply or speed control of a DC motor.  
The MB3788 is compatible with all master ICs producing triangular waves, saw-tooth waves and sine waves with  
an amplitude of 1.3 V to 1.9 V.  
It can be used in high-performance portable equipment such as a video camcorder or notebook personal computer  
(word processor).  
FEATURES  
• Wide operating power supply voltage range: 3.6 V to 18 V  
• Low power dissipation  
• Operating: 1.9 mA (standard)  
Standby: 10 µA Max  
(Continued)  
PACKAGE  
24-pin Plastic SSOP  
(FPT-24P-M03)  
This device contains circuitry to protect the inputs against damage due to high static voltages or electric fields. However, it is  
advised that normal precautions be taken to avoid application of any voltage higher than maximum rated voltages to this high  
impedance circuit.  
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MB3788  
PIN DESCRIPTION  
Pin No.  
Pin name  
I/O  
O
I
Descriptions  
Channel 1 push-pull type output  
Channel 1 output current setting  
2
3
OUT1  
VE1  
4
Ca1  
O
I
Channel 1 output transistor OFF current setting: Output transistor OFF  
The current is set by connecting a capacitor between pins Ca1 and Cb1.  
5
Cb1  
Channel 1  
Channel 1 error amplifier output  
6
FB1  
Channel 1 error amplifier inversion input  
Channel 1 error amplifier non-inversion input  
Channel 1 comparator inversion input  
Channel 2 comparator inversion input  
Channel 2 error amplifier non-inversion input  
Channel 2 error amplifier inversion input  
Channel 2 error amplifier output  
7
-IN1(E)  
+IN1(E)  
-IN1(C)  
-IN2(C)  
+IN2(E)  
-IN2(E)  
FB2  
8
9
I
I
16  
17  
18  
19  
20  
21  
22  
23  
I
I
O
I
Channel 2  
Ca2  
Channel 2 output transistor OFF current setting: Output transistor OFF  
The current is set by connecting a capacitor between pins Ca2 and Cb2.  
Cb2  
VE2  
Channel 2 output current setting  
Channel 2 push-pull type output  
OUT2  
O
Power and channel 1 control pin  
H level: Power and channel 1 operating  
L level: Standby  
13  
14  
CTL1  
I
I
Control  
circuit  
Channel 2 control pin  
When CTL1 pin = H level,  
H level: Channel 2 operating  
L level: Channel 2 OFF  
CTL2  
SCP  
Short-circuit protection circuit capacitor connection  
Output circuit power pin  
15  
1
I
2
VCC  
Master oscillating waveform input  
Reference power and control circuit power  
Reference voltage output  
10  
11  
12  
24  
-IN(PWM)  
VCC1  
Power  
circuit  
O
VREF  
Ground  
GND  
Note: The alphabetic characters in parenthesis above indicate the following input pins.  
(C): Comparator  
(E): Error amplifier  
3
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MB3788  
BLOCK DIAGRAM  
Cb1  
Channel 1  
4
5
Ca1  
Error amplifier 1  
OFF current setting  
+
-
1
2
3
VCC(out)  
+IN1 (E)  
-IN1 (E)  
FB1  
8
7
6
PWM comparator 1  
+
-
OUT1  
VE1  
Comparator 1  
+
-
0.6 V  
1.5 V  
9
-IN1 (C)  
Ca2  
Cb2  
Channel 2  
20  
21  
Error amplifier 2  
OFF current setting  
+
-
+IN2 (E) 17  
PWM comparator 2  
+
-
18  
-IN2 (E)  
OUT2  
VE2  
23  
22  
19  
FB2  
Comparator 2  
+
-
0.6 V  
1.5 V  
16  
-IN2 (C)  
SCP comparator  
CTL2  
14  
-
-
+
1.9 V  
1.3 V  
Timer circuit  
1 µA  
2.1 V  
VCC  
11  
SCP  
VREF  
15  
Low input  
Power/channel  
ON/OFF  
Reference  
voltage  
power (2.5 V)  
SR latch  
circuit  
voltage  
protection  
circuit  
13 CTL1  
circuit  
10  
12  
24  
-IN(PWM)  
VREF  
GND  
4
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MB3788  
FUNCTIONAL DESCRIPTION  
1. Major Functions  
(1) Reference voltage power circuit  
The reference voltage power supply produces a reference voltage (2.50 V) which is temperature-compensated  
by the voltage supplied from the power pin (pin 11); it is used as the IC internal circuit operating power supply.  
The reference voltage can also be output externally at 1 mA from VREF pin (pin12).  
(2) Error amplifier  
The error amplifier detects the switching regulator output voltage and outputs a PWM control signal. It has a  
wide in-phase input voltage range of -0.2 V to VCC - 1.8 V to make setting from an external power supply easy.  
Connecting the output pin and inversion input pin of the error amplifier through a feedback resistor and capacitor  
allows setting of any loop gain to provide stable phase compensation.  
(3) PWM comparator  
The PWM comparator controls the output pulse ON time according to the input voltage.  
The voltage input to the -IN pin (PWM) turns the output transistor on when it is lower than the output voltage of  
the error amplifier.  
(4) Output circuit  
The output circuit is configured in a push-pull form and uses a PNP transistor drive system to drive a transistor  
of up to 30 mA. (See How to Set Output Current.)  
2. Channel Control Function  
Channels can be set ON/OFF by combining the voltage levels at pin CTL1 (pin 13) and pin CTL2 (pin 14).  
Channel ON/OFF Setting Conditions  
Voltage level at CTL pin  
Channel ON/OFF status  
Channel 1  
CTL1  
CTL2  
Power circuit  
Channel  
L
×
H
L
Stand by state*  
H
ON  
ON  
OFF  
*: The power current in the standby state is 10 µA Max.  
5
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MB3788  
3. Protection Functions  
(1) Timer and latch-type short-circuit protection circuit  
The SCP comparator detects the output voltage levels of two comparators to detect an output short circuit. If  
the output voltage of one comparator increases to 2.1 V, the transistor of the timer circuit is turned off and the  
short circuit protection capacitor connected externally to the SCP pin (pin 15) starts charging.  
The latch circuit turns off the output transistor and simultaneously clears the duty cycle to 0 when the output  
voltage level of the comparator does not return to the normal voltage level until the capacitor voltage rises to the  
base-emitter junction voltage VBE (0.65 V) of the transistor. (See How to Set Time Constant for Timer & Latch-  
Type Short-Circuit Protection Circuit.)  
When the protection circuit operates, recycle the power to reset the circuit.  
(2) Low input voltage malfunction fail-safe circuit  
A transient at power-on, or an instantaneous supply voltage drop can cause a control IC malfunction, which may  
damage the system. The low input voltage malfunction fail-safe circuit detects the internal reference voltage  
level based on the supply voltage level, resets the latch circuit, turns off the output transistor, clears the duty  
cycle to 0 and holds the SCP pin (pin 15) at Low level. All circuits are recovered when the supply voltage is  
greater than the threshold voltage of the fail-safe circuit.  
6
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MB3788  
ABSOLUTE MAXIMUM RATINGS  
(TA = +25°C)  
Ratings  
Parameter  
Supply voltage  
Symbol  
Conditions  
Unit  
Min  
Max  
20  
VCC  
VICTL  
PD  
V
V
Control input voltage  
Allowable loss  
20  
Ta +25°C  
500*  
+85  
mW  
°C  
°C  
Operating ambient temperature  
Storage temperature  
TOP  
Tstg  
-30  
-55  
+125  
*: Value obtained when mounted on 4 cm × 4 cm double-sided epoxy substrate  
WARNING: Semiconductor devices can be permanently damaged by application of stress (voltage, current,  
temperature, etc.) in excess of absolute maximum ratings. Do not exceed these ratings.  
RECOMMENDED OPERATING CONDITIONS  
(TA = +25°C)  
Values  
Typ  
6.0  
Parameter  
Supply voltage  
Symbol Conditions  
Unit  
Min  
3.6  
-1  
Max  
18  
VCC  
IOR  
VI  
V
mA  
V
Reference voltage output current  
Error amplifier input voltage  
Error amplifier input voltage  
Control input voltage  
0
-0.2  
-0.2  
-0.2  
3.0  
100  
-30  
VCC - 1.8  
VCC  
18  
VI  
V
VICTL  
IO  
V
Output current  
30  
mA  
kHz  
°C  
Operating frequency  
fosc  
Top  
300  
25  
1000  
85  
Operating ambient temperature  
WARNING: The recommended operating conditions are required in order to ensure the normal operation of the  
semiconductor device. All of the device’s electrical characteristics are warranted when the device is  
operated within these ranges.  
Always use semiconductor devices within their recommended operating condition ranges. Operation  
outside these ranges may adversely affect reliability and could result in device failure.  
No warranty is made with respect to uses, operating conditions, or combinations not represented on  
the data sheet. Users considering application outside the listed conditions are advised to contact their  
FUJITSU representatives beforehand.  
7
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MB3788  
ELECTICAL CHARACTERISTICS  
(VCC =6V, TA = +25°C)  
Value  
Parameter  
Symbol  
Conditions  
IOR = -1 mA  
Unit  
Min  
Typ  
Max  
Reference voltage  
VREF  
2.475  
2.500  
2.525  
V
Output voltage temperature  
variation  
VREF/  
TA = -30° to +85°C  
-2  
±0.2  
2
%
VREF  
Reference  
voltage  
Input stability  
Line  
Load  
IOS  
VCC = 3.6 V to 18 V  
2
10  
10  
mV  
mV  
mA  
V
Load stability  
IOR = -0.1 mA to 1 mA  
3
Short-circuit output current  
VREF = 2 V  
-20  
-8  
-3  
VtH  
2.65  
2.45  
200  
1.9  
0.65  
-100  
Threshold voltage  
Low voltage  
malfunction  
fail-safe  
VtL  
V
Hysteresis width  
VHYS  
VR  
80  
mV  
V
circuit  
Reset voltage  
1.5  
0.58  
-200  
-0.2  
0.60  
Input offset voltage  
Input bias current  
VIO  
0.72  
V
Short-circuit  
detection  
comparator  
IIB  
VI = 0 V  
nA  
V
In-phase input voltage range  
Threshold voltage  
VICM  
VtPC  
VSTB  
VI  
VCC-1.8  
0.70  
100  
100  
-0.6  
10  
0.65  
50  
V
Input standby voltage  
Input latch voltage  
Input source current  
Input offset voltage  
Input offset current  
Input bias current  
mV  
mV  
µA  
mV  
nA  
nA  
V
Short-circuit  
detector  
50  
IIbpc  
VIO  
-1.4  
-10  
-100  
-200  
-0.2  
60  
-1.0  
VFB = 1.6 V  
VFB = 1.6 V  
VFB = 1.6 V  
IIO  
100  
IIB  
-60  
In-phase input voltage range  
Voltage gain  
VICM  
AV  
VCC-1.8  
100  
800  
80  
dB  
kHz  
dB  
V
Error  
amplifier  
Frequency bandwidth  
In-phase signal rejection ratio  
BW  
CMRR  
VOM+  
VOM-  
IOM+  
IOM-  
AV = 0 dB  
60  
VREF-0.3  
2.4  
0.05  
120  
-2  
Maximum output voltage width  
0.5  
V
Output sink current  
VFB = 1.6 V  
VFB = 1.6 V  
µA  
mA  
Output source current  
(Continued)  
8
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MB3788  
(Continued)  
Values  
Parameter  
Symbol  
Conditions  
Unit  
Min  
1.05  
Typ  
1.3  
1.9  
120  
-2  
Max  
Vt0  
Duty cycle = 0 %  
V
Threshold voltage  
Vt100  
IIM+  
IIM-  
IIB  
Duty cycle = 100 %  
2.25  
V
PWM  
comparator  
Input sink current  
Input source current  
Input bias current  
Threshold voltage  
µA  
mA  
µA  
V
VI = 0 V  
-1.0  
0.7  
-0.5  
1.4  
100  
Vth  
IIH  
2.1  
200  
10  
Control  
VCTL = 5 V  
VCTL = 0 V  
µA  
µA  
mA  
mA  
µA  
µA  
mA  
Input current  
IIL  
-10  
Source current  
IO  
-40  
30  
Output  
Sink current  
IO  
RB = 50 Ω  
VO = 18 V  
18  
42  
Output leak current  
Standby current  
ILO  
ICCO  
ICC  
20  
0
10  
All devices  
Power current at output OFF  
1.9  
2.7  
9
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MB3788  
STANDARD CHARACTERISTIC CURVES  
1. Power current - supply voltage characteristic  
2. Reference voltage - supply voltage characteristic  
TA = +25°C  
TA = +25°C  
2.5  
2.0  
1.5  
CTL1 = 6 V  
5
4
3
2
1
0
CTL1, 2 = 6 V  
Reference  
voltage  
VREF (V)  
Power  
current  
lCC (mA)  
1.0  
0.5  
0
0
4
8
12 16 20  
0
4
8
12 16 20  
Supply voltage VCC (V)  
Supply voltage VCC (V)  
3.Reference voltage, output current setting pin voltage  
- supply voltage characteristic  
4. Reference voltage - ambient temperature characteristic  
2.56  
TA = +25°C  
VCC = 6 V  
VCTL1, 2 = 6 V  
IOR = -1 mA  
5
4
3
2
1
0
5
4
Reference  
voltage  
VREF (V)  
2.54  
2.52  
2.50  
2.48  
2.46  
2.44  
VREF  
Reference  
voltage  
VREF (V)  
3
2
1
0
Output  
current  
setting  
pin voltage  
VE (V)  
VE  
-60 -40 -20  
0
20 40 60 80 100  
Ambient temperature TA (°C)  
0
1
2
3
4
5
Supply voltage VCC (V)  
5. Reference voltage - control voltage characteristic  
VCC = 6 V  
6. Control current - control voltage characteristic  
VCC = 6 V  
TA = +25°C  
500  
400  
300  
200  
100  
0
TA = +25°C  
3.0  
2.8  
Reference  
Control  
current  
voltage  
VREF (V)  
2.6  
2.4  
2.2  
2.0  
lCTL1 (µA)  
0
1
2
3
4
5
0
4
8
12 16  
20  
Control voltage VCTL1 (V)  
Control voltage VCTL1 (V)  
(Continued)  
10  
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MB3788  
(Continued)  
8.Gain - frequency characteristic and phase - frequency  
7. Duty - input oscillating frequency characteristic  
characteristic  
100  
80  
Input waveform  
VCC = 6 V  
VFB = 1.6 V  
TA = +25°C  
TA = +25°C  
180  
90  
40  
20  
1.9V  
1.3V  
60  
Duty  
Gain  
(dB)  
Phase  
φ (deg)  
Dtr (%)  
0
40  
0
20  
-90  
-20  
-40  
0
0
-180  
5K 10K  
50K 100K  
500K 1M  
Input oscillating frequency (Hz)  
1K  
10K  
100K  
f (Hz)  
1M  
5M 10M  
9. Power dissipation - ambient temperature characteristic  
1000  
Circuit for measuring gain - frequency characteristic and  
phase - frequency characteristic  
VCC = 6 V  
2.5 V  
2.5 V  
240 kΩ  
800  
600  
4.7 k4.7 kΩ  
10 µF  
Power  
dissipation  
PD (mW)  
-
out  
+
-
400  
+
in  
Error amplifier  
200  
0
4.7 kΩ  
4.7 kΩ  
-20 020 406080 100  
Ambient temperature TA (°C)  
11  
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MB3788  
HOW TO SET OUTPUT VOLTAGE  
VREF  
VOUT  
VREF  
2 × R2  
VOUT =  
(R1 + R2)  
R
R1  
+
-
R
R2  
RNF  
Note: Set the output voltage in the positive range (VOUT > 0).  
12  
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MB3788  
HOW TO SET OUTPUT CURRENT  
The output circuit is configured in a push-pull type as shown in Figure 1. The ON current value of the output  
current waveform shown in Figure 2 is a constant current and the OFF value set by RE is set by a time constant.  
Each output current can be calculated from the following expression:  
• ON current = 1.5/RE (A) (Output current setting pin voltage: VE 1.5 V)  
• The OFF current time constant is proportional to the value of CB.  
Drive Tr  
ON current  
CB  
OFF  
current  
OFF current  
setting part  
Output  
0
current  
ON current  
OFF current  
RE  
VE  
t
Fig.1 Output Circuit Diagram  
Fig.2 Output Current Waveform  
1000 pF  
VCC  
Iout  
-IN1 (C)  
(5 V)  
4
5
22 µH  
10 µF  
1
8.2 kΩ  
2.7 kΩ  
Vout  
2
MB3788  
1000 pF  
-IN1 (E)  
3
150 Ω  
Fig.3 Output Pin Voltage and Current Waveforms (Channel 1)  
Fig.4 Measurement Circuit Diagram  
13  
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MB3788  
HOW TO SET TIME CONSTANT FOR TIMER & LATCH-TYPE SHORT-CIRCUIT  
PROTECTION CIRCUIT  
If the load conditions of the switching regulator are stable, the outputs of comparators 1 and 2 do not change,  
so the SP comparator outputs a High level. At this time, the SCP pin (pin 15) is held at about 50 mV.  
If the load conditions change suddenly due to a load short-circuit, for example, the output voltage of the com-  
parator of the channel becomes a High-level signal (more than 2.1 V). Then, the SVP comparator outputs a  
Low level and transistor Q1 is turned off. The short-circuit protection capacitor CPE externally connected to the  
SCP pin starts to charge.  
VPE = 50 mV + tPE × 10-6/CPE  
0.65 = 50 mV + tPE × 10-6/CPE  
CPE = tPE /0.6 (s)  
Once the capacitor CPE is charged to about 0.65 V, the SR latch is set and the output drive transistor is turned  
off. At this time, the duty cycle is made low and the output voltage of the SCP pin (pin 15) is held at Low level.  
This closes the SR latch input to discharge CPE.  
2.5 V  
1 µA  
15  
S
R
Low  
input  
voltage  
protection  
circuit  
PWM  
comparator  
OUT  
-
-
+
Comparator 1  
Comparator 2  
SR latch-type  
circuit  
Q2  
CPE  
Q1  
2.1 V  
Fig. 5 Latch-Type Short-Circuit Protection Circuit  
14  
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MB3788  
PROCESSING WITHOUT USING SCP PIN  
If the timer and latch-type short-circuit protection circuit is not used, connect the SCP pin (pin 15) to GND as  
close as possible. Also, connect the input pin of each channel comparator to the VCC pin (pin 11).  
11  
VCC  
9
-IN1 (C)  
16  
-IN2 (C)  
GND  
SCP  
15  
24  
Fig. 6 Processing without using SCP Pin  
15  
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MB3788  
EQUIVALENT SERIES RESISTANCE OF SMOOTHING CAPACITOR AND STABILITY OF  
DC/DC CONVERTER  
The equivalent series resistance (ESR) of the smoothing capacity in a DC/DC converter has a great effect on  
the loop phase characteristics.  
The ESR causes a small delay at the capacitor with a series resistance of 0 (Figures 8 and 9), thus improving  
system stability. On the other hand, using a smoothing capacitor with a low ESR reduces system stability.  
Therefore, attention should be paid to using semiconductor electrolytic capacitors (such as OS capacitors) or  
tantalum capacitors with a low ESP. (Phase margin reduction by using an OS capacitor is explained on the next  
page.)  
L
Tr  
RC  
VIN  
D
RL  
C
Fig. 7 Basic Voltage-Drop Type DC/DC Converter Circuit  
20  
0
0
(2)  
Phase  
(deg)  
-90  
Gain  
(dB)  
-20  
-40  
-60  
(2)  
(1)  
(1): RC = 0 Ω  
(2): RC = 31 mΩ  
(1): RC = 0 Ω  
(2): RC = 31 mΩ  
(1)  
-180  
10  
100  
1k  
Frequency f (Hz)  
10k  
100k  
10  
100  
1k  
10k  
100k  
Frequency f (Hz)  
Fig.8 Gain - Frequency Characteristic  
Fig.9 Phase - Frequency Charecteristic  
16  
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MB3788  
(Reference Data)  
The phase margin is halved by changing the smoothing capacitor from an aluminum electrolytic capacitor (Rc  
= 1.0 ) to a semiconductor electrolytic capacitor (OS capacitor: Rc = 0.2 ) with a low ESR (Figures 11 and 12).  
VOUT  
VO+  
CNF  
AV - φ characteristic between VOUT and VIN  
R2  
-IN  
+IN  
+
-
VIN  
FB  
R1  
VREF/2  
Error amplifier  
Fig. 10 DC/DC Converter AV - φ Characteristic Measurement Diagram  
Aluminum electrolytic capacitor gain - frequency and phase - frequency characteristics (DC/DC converter +5 V output)  
60  
VCC = 10 V  
RL = 25 Ω  
180  
90  
CP = 0.1 µF  
40  
20  
AV  
ϕ⇒  
VO+  
Gain  
(dB)  
+
-
62°  
Phase  
0
0
(deg)  
GND  
-90  
-20  
Aluminum electrolytic capacitor  
220 µF (16 V)  
-180  
-40  
Rc 1.0 : fOSC = 1 kHz  
101001 k 10 k 100 k  
Frequency f (Hz)  
Fig. 11 Gain - Frequency Characteristic  
OS capacitor gain - frequency and phase - frequency characteristics (DC/DC converter +5 V output)  
VCC = 10 V  
60  
40  
20  
AV  
RL = 25 Ω  
CP = 0.1 µF  
180  
90  
VO+  
ϕ⇒  
Gain  
(dB)  
+
-
Phase  
(deg)  
0
0
27°  
GND  
-20  
-90  
OS capacitor  
22 µF (16 V)  
Rc 1.2 : fOSC = 1 kHz  
-40  
-180  
101001 k 10 k 100 k  
Frequency f (Hz)  
Fig.12 Phase - Frequency Characteristic Curves  
17  
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MB3788  
APPLICATION CIRCUIT  
10 µH  
VCC  
+
-
+
-
33 µF  
33 µF  
11  
13  
14  
VCC  
CTL2  
CTL1  
4.7 kΩ  
8
<Logic power supply>  
(a)  
Cb1  
Ca1  
4
5
1
2
3
+IN1 (E)  
1000 pF  
4.7 kΩ  
8.2 kΩ  
(a)  
Channel 1  
(dB)  
7
-IN1 (E)  
22 µH  
5 V  
VCC(out)  
OUT1  
VE1  
100 kΩ  
0.22 µF  
2.7 kΩ  
+
-
6
10 µF  
FB1  
150 Ω  
(15 mA)  
9
-IN1 (C)  
<Logic power supply>  
(b)  
4.7 kΩ  
4.7 kΩ  
+IN2 (E)  
-IN2 (E)  
17  
18  
20  
21  
23  
22  
Ca2  
Cb2  
1000 pF  
3.8 kΩ  
2.7 kΩ  
22 µH  
3 V  
(b)  
Channel 2  
(deg)  
+
-
100 kΩ  
0.22 µF  
OUT2  
VE2  
10 µF  
FB2  
19  
150 Ω  
-IN2 (C)  
16  
VREF SCP  
-IN(PWM)  
GND  
24  
10  
15  
12  
0.1 µF  
Triangular wave signal  
1.9 V  
1.3 V  
CT  
<Analog power supply>  
+15 V  
+24 V  
<Sensor power supply>  
<DC motor speed control>  
<DC motor speed control>  
<MB3785A-used DC/DC converter>  
DC motor 1  
DC motor 2  
18  
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MB3788  
NOTES ON USE  
Take account of common impedance when designing the earth line on a printed wiring board.  
Take measures against static electricity.  
- For semiconductors, use antistatic or conductive containers.  
- When storing or carrying a printed circuit board after chip mounting, put it in a conductive bag or container.  
- The work table, tools and measuring instruments must be grounded.  
- The worker must put on a grounding device containing 250 kto 1 Mresistors in series.  
• Do not apply a negative voltage  
- Applying a negative voltage of 0.3 V or less to an LSI may generate a parasitic transistor, resulting in  
malfunction.  
ORDERING INFORMATION  
Part number  
MB3788PFV  
Package  
Remarks  
24-pin Plastic SSOP  
(FPT-24P-M03)  
19  
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MB3788  
PACKAGE DIMENSION  
Note 1) *1 : Resin protrusion. (Each side : +0.15 (.006) Max) .  
Note 2) *2 : These dimensions do not include resin protrusion.  
Note 3) Pins width and pins thickness include plating thickness.  
Note 4) Pins width do not include tie bar cutting remainder.  
24-pin plastic SSOP  
(FPT-24P-M03)  
1
0.17±0.03  
(.007±.001)  
*
7.75±0.10(.305±.004)  
24  
13  
*25.60±0.10 7.60±0.20  
(.220±.004) (.299±.008)  
INDEX  
Details of "A" part  
1.25 +0.20  
–0.10  
(Mounting height)  
.049 +.008  
–.004  
0.25(.010)  
0~8˚  
"A"  
1
12  
0.24 +0.08  
.009 +.003  
–0.07  
0.65(.026)  
M
0.13(.005)  
–.003  
0.50±0.20  
0.10±0.10  
(.020±.008)  
(.004±.004)  
(Stand off)  
0.60±0.15  
(.024±.006)  
0.10(.004)  
C
2003 FUJITSU LIMITED F24018S-c-4-5  
Dimensions in mm (inches) .  
Note : The values in parentheses are reference values.  
20  
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MB3788  
FUJITSU LIMITED  
All Rights Reserved.  
The contents of this document are subject to change without notice.  
Customers are advised to consult with FUJITSU sales  
representatives before ordering.  
The information, such as descriptions of function and application  
circuit examples, in this document are presented solely for the  
purpose of reference to show examples of operations and uses of  
Fujitsu semiconductor device; Fujitsu does not warrant proper  
operation of the device with respect to use based on such  
information. When you develop equipment incorporating the  
device based on such information, you must assume any  
responsibility arising out of such use of the information. Fujitsu  
assumes no liability for any damages whatsoever arising out of  
the use of the information.  
Any information in this document, including descriptions of  
function and schematic diagrams, shall not be construed as license  
of the use or exercise of any intellectual property right, such as  
patent right or copyright, or any other right of Fujitsu or any third  
party or does Fujitsu warrant non-infringement of any third-party’s  
intellectual property right or other right by using such information.  
Fujitsu assumes no liability for any infringement of the intellectual  
property rights or other rights of third parties which would result  
from the use of information contained herein.  
The products described in this document are designed, developed  
and manufactured as contemplated for general use, including  
without limitation, ordinary industrial use, general office use,  
personal use, and household use, but are not designed, developed  
and manufactured as contemplated (1) for use accompanying fatal  
risks or dangers that, unless extremely high safety is secured, could  
have a serious effect to the public, and could lead directly to death,  
personal injury, severe physical damage or other loss (i.e., nuclear  
reaction control in nuclear facility, aircraft flight control, air traffic  
control, mass transport control, medical life support system, missile  
launch control in weapon system), or (2) for use requiring  
extremely high reliability (i.e., submersible repeater and artificial  
satellite).  
Please note that Fujitsu will not be liable against you and/or any  
third party for any claims or damages arising in connection with  
above-mentioned uses of the products.  
Any semiconductor devices have an inherent chance of failure. You  
must protect against injury, damage or loss from such failures by  
incorporating safety design measures into your facility and  
equipment such as redundancy, fire protection, and prevention of  
over-current levels and other abnormal operating conditions.  
If any products described in this document represent goods or  
technologies subject to certain restrictions on export under the  
Foreign Exchange and Foreign Trade Law of Japan, the prior  
authorization by Japanese government will be required for export  
of those products from Japan.  
F0309  
FUJITSU LIMITED Printed in Japan  
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