3/4

REV. B

〇Package Dimensions

〇Block Diagram

〇Pin Description

Pin No.

Pin Name

Function

1

DUTY

Control PWM mode and BURST mode

2

BRT

External resistor from BRT to GND for adjusting

the BURST triangle oscillator

3

BCT

External capacitor from BCT to GND for adjusting

the BURST triangle oscillator

4

RDIS

External resistor from RDIS to GND for adjusting

the triangle oscillator

5

RT

External resistor from SRT to RT for adjusting

the triangle oscillator

6

SRT

External resistor from SRT to RT for adjusting

the triangle oscillator

7

CT

External capacitor from CT to GND for adjusting

the triangle oscillator

8

GND

GROUND

9

FB1

Error amplifier output①

10

IS1

Error amplifier input①

11

VS1

Error amplifier input②

12

FB2

Error amplifier output②

13

IS2

Error amplifier input③

14

VS2

Error amplifier input④

15

FAIL

Protect clock output

16

STB

Stand-by switch

17

COMP1

Under, over voltage detect for 1ch

18

COMP2

Under, over voltage detect for 1ch

19

REG

Internal regulator output

20

SS

External capacitor from SS to GND for Soft Start

Control

21

SCP1

External capacitor from SCP1 to GND for Timer

Latch for 1ch

22

SCP2

External capacitor from SCP2 to GND for Timer

Latch for 2ch

23

P2

FET driver for 2ch

24

N2

FET driver for 2ch

25

PGND

Ground for FET drivers

26

N1

FET driver for 1ch

27

P1

FET driver for 1ch

28

Vcc

Supply voltage input

SSOP-B28 (Unit:mm)

BD9766FV

Lot No.

Device Mark

１

STB

BLOCK

SYSTEM　ON/OFF

OSC

BOSC

CT

VCC

RT

BRT BCT

DUTY

P1

N1

STB

IS1

DUTY

BLOCK

REG

BLOCK

UVLO

BLOCK

VCC

REG

F/B

BLOCK①

PWM

BLOCK①

LOGIC

BLOCK

①

OUTPUT

BLOCK①

SS

CT

VS1

SS

FB1

P2

N2

IS2

F/B

BLOCK②

PWM

BLOCK②

SS

CT

VS2

FB2

FAIL

PROTECT

BLOCK

GND

PGND

COMP1 COMP2

SCP2

SRT

VCC

VCC

RDIS

SCP1

LOGIC

BLOCK

②

OUTPUT

BLOCK②

(Include BURR 10.35)