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〇Package Dimensions
〇Pin Description
Pin No.
PinName
Function
Device Mark
1
COMP_A
Over voltage detect for 1ch,2ch
2
3
4
5
6
7
NA1
NB1
FET driver for 1ch
FET driver for 1ch
Ground for FET drivers
FET driver for 2ch
FET driver for 2ch
Stand-by switch
BD9892K
PGND_A
NB2
NA2
STB
8
VCC_A
Supply voltage input
Reference voltage input for IS error
amplifier
9
VREF
10
11
FAIL
PH
Protect clock output
Shift control input
Lot No.
12
13
REG
Internal regulator output
DUTY
Control PWM mode and BURST mode
External resistor from BRT to GND for
adjusting the BURST triangle oscillator
External capacitor from BCT to GND for
adjusting the BURST triangle oscillator
for 3ch,4ch
14
BRT
15
BCT_B
QFP44 (unit:mm)
External capacitor from BCT to GND for
adjusting the BURST triangle oscillator
for 1ch,2ch
16
BCT_A
17
18
GND
CT
GROUND
External capacitor from CT to GND for
adjusting the triangle oscillator
External resistor from RT to GND for
adjusting the triangle oscillator
External resistor from SRT to RT for
adjusting the triangle oscillator
External capacitor from CP to GND for
Timer Latch for 1ch,2ch
19
20
21
22
RT
〇Block Diagram
SRT
VCC_A VCC_B REG VREF
CT
RT
BRT BCT_A
BCT_B
DUTY
PH
CP_A
CP_B
OSC
BLOCK
BOSC
BLOCK
DUTY
BLOCK
REG
BLOCK
External capacitor from CP to GND for
Timer Latch for 3ch,4ch
STB
BLOCK
SYSTEMꢀON/OFF
STB
External capacitor from SSto GND for Soft
Start Control 1ch,2ch
23
24
SS_A
SS_B
UVLO
BLOCK
VCC
SS_A
SS_B
UVLO
External capacitor from SSto GND for Soft
Start Control 3ch,4ch
FB1
VCC_A
25
26
27
28
29
30
31
32
33
VCC_B
UVLO
NA4
Supply voltage input
NA1
NB1
IS1
F/B
LOGIC
OUTPUT
BLOCK①
PWM
SS_A
CT
BLOCK①
External Under Voltage Lock OUT
FET driver for 4ch
BLOCK①
BLOCK①
VS1
NB4
FET driver for 4ch
FB2
VCC_A
NA2
NB2
PGND_B
NB3
Ground for FET drivers
OUTPUT
BLOCK②
IS2
F/B
PWM
BLOCK②
LOGIC
SS_A
CT
BLOCK②
BLOCK②
FET driver for 3ch
VS2
NA3
FET driver for 3ch
PGND_A
COMP_B
VS4
Over voltage detect for 3ch,4ch
Error amplifier input④
FB3
VCC_B
IS3
NA3
NB3
PWM
BLOCK③
LOGIC
BLOCK③
OUTPUT
BLOCK③
F/B
BLOCK③
SS_B
CT
VS3
34
35
36
37
38
39
40
41
42
43
44
IS4
FB4
VS3
IS3
FB3
FB2
IS2
VS2
FB1
IS1
VS1
Error amplifier input④
Error amplifier output④
Error amplifier input③
Error amplifier input③
Error amplifier output③
Error amplifier output②
Error amplifier input②
Error amplifier input②
Error amplifier output①
Error amplifier input①
Error amplifier input①
FB4
VCC_B
IS4
NA4
NB4
OUTPUT
BLOCK④
F/B
PWM
BLOCK④
LOGIC
BLOCK④
SS_B
CT
VS4
BLOCK④
PGND_B
GND
PROTECT
BLOCK
FAIL
COMP_A
COMP_B
CP_A
CP_B
SRT
REV. B