MB3875 Datasheet, PDF (19/27 Pages) Fujitsu Component Limited. – DC/DC Converter IC for Charging

s APPLICATION EXAMPLE
MB3875/MB3877
R10
22 kΩ
−INE1
11
OUTC1
R4
∗2
C10 3900 pF 10
+INC1
<Current Amp.1>
13
+
R5
330 kΩ
R11
−INC1
12
30 kΩ 150 kΩ
× 25
−
R9
R6
68 kΩ
+INE1 ⁸
FB1
9
−INE2 ₆
R8 100 kΩ
C8
3900 pF
150 kΩ
OUTC2 ₄
+INC2 ^{<Current Amp.2>}
A
24
+
R7 _−INC2
R12
B
1
× 25
−
22 kΩ
R14
1.3 kΩ
+INE2
7
R16
200 kΩ
Q2
30 kΩ
R13
110 Ω
R15
FB2
3
SW1
IN3
2
<Error
Amp.1>
VREF
−
+
<Error
Amp.2>
VREF
−
+
<PWM
Comp.>
+++−
<OUT>
Drive
VCC (O)
21
C5
0.1 µF
OUT
20
C1
22 µF
AB
Q1
BATT
∗4
L1
RS
27 µH
0.033 Ω
VCC
C2 C3
100 µF 100 µF
Bias voltage
VH
block
19
<VH> ^{(VCC − 5 V)}
D1
VIN
∗3
−INE3
∗1
<Error
Amp.3>
VREF
<UVLO>
VCC
(VCC UVLO) 215 kΩ
16
−
C6
3900 pF
50 kΩ
+
+
35 kΩ
200 kΩ
R3
FB3
15
<SOFT>
VREF
VREF
(4.2 V)
0.91 V
(0.77 V)
VREF
ULVO
1 µA
CS
2200 pF
CS
22
2.5 V
1.5 V
<OSC>
VCC
bias
<REF> <CTL>
VCC
18
CTL
14
C7
0.1 µF
(45 pF)
17
5
RT VREF
RT 47 kΩ
23
GND
C9
0.1 µF
∗ 1 : MB3875 100 kΩ
MB3877 150 kΩ
∗ 2 : Vin = 16 V 0 Ω
Vin = 19 V 82 kΩ
∗ 3 : MB3875 16 V/19 V
MB3877 19 V
∗ 4 : MB3875 12.6 V
MB3877 16.8 V
19