MB3881 Datasheet, PDF (5/40 Pages) Fujitsu Component Limited. – 8-ch DC/DC Converter IC with Synchronous Rectifier for Voltage Step-up and Step-down

s BLOCK DIAGRAM
• General view
FB1 47
−IN1 46
DTC1 48
Error
− ^Amp.1
+
+
1.25 V
SCP
− ^Comp.1
+
+
1.0 V
PWM
Comp.1-1
+
+
−
PWM
VB1 Comp.1-2
+
−
CH1
Drive
1-1
Drive
1-2
58 VCC(O)-1
50 OUT1-1
49 VSS(O)-1
52 VDD(O)
51 OUT1-2
FB2 44
−IN2 43
Error
− ^Amp.2
+
+
1.25 V
SCP
Comp.2
−
+
+
PWM
Comp.2-1
+
+
−
PWM
VB2 Comp.2-2
+
−
CH2
Drive
2-1
Drive
2-2
53 OUT2-1
54 OUT2-2
1.0 V
DTC2 45
A
PWM
Comp.3
CH3
FB3 41
+
+
−IN3 40
Error
− ^Amp.3
−
+
Drive
3
56 OUT3
+
1.25 V
SCP
Comp.3
−
+
+
1.0 V
DTC3 42
FB4 38
−IN4 37
DTC4 39
Error
− ^Amp.4
+
+
1.25 V
SCP
Comp.4
−
+
+
1.0 V
FB5 20
−IN5 21
−IN5(C) 23
+IN5 22
DTC5 19
Error
− ^Amp.5
+
+
0.6 V SCP
Comp.5
−
+
PWM
Comp.4
+
+
−
PWM
Comp.5
+
+
−
CH4
Drive
4
CH5
Drive
5
57 OUT4
55 GND(O)-1
59 VCC(O)-2
60 OUT5
63 VSS(O)-2
FB6 14
−IN6 15
Error
− ^Amp.6
+
+
PWM
Comp.6
+
+
−
CH6
Drive
6
61 OUT6
0.6 V SCP
B
Comp.6
−IN6(C) 17
−
+IN6 16
+
OVP 18
DTC6 13
FB7 10
−IN7 11
+IN7 12
20 kΩ
80 kΩ
DTC7 9
Error
− ^Amp.7
+
+
+
1.25 V
SCP
Comp.7
−
+
+
+
1.0 V
PWM
Comp.7
+
+
−
CH7
Drive
7
62 OUT7
FB8 4
−IN8 5
+IN8 6
−IN8(C) 7
+IN8(C) 8
Error
− ^Amp.8
+
SCP
Comp.8
−
+
PWM
Comp.8
−
−
+
CH8
Drive
8
64 OUT8
2 RB8
DTC8 3
1 GND(O)-2
C
CTL
1, 3, 4
CTL-2 29
CS CTL
CTL-3 30
Logic
CTL-4 31
Buff
Buff ×0.8
CT1 _{1.73 V}
1.0 V
CT2 _{1.73 V}
1.0 V
CT _{0.8 V}
0.3 V
CS 32
UVLO
27 VCC
VB 36
2V
OSC
SCP
35 33 34
SYNC RT CT
26
CSCP
Power
Ref ON/OFF
CTL
2.5 V
24 25
VREF GND
28 CTL-1 H : ON (Power/CH1, 3, 4, 8)
L : OFF (Standby mode)
(64 pin)
MB3881
5