R2A20124AFP/R2A20124ASP

Preliminary

REJ03D0928-0200 Rev.2.00

Page 4 of 12

Aug 03, 2010

Pin Functions

LQFP-40

Pin No.

SOP-20

Pin No.

Pin Name

Input/Output

Pin Function

1

8

DELAY-1

Input/Output

Delay time adjustor for the full-bridge control signal (OUT-A and B)

2

9

DELAY-2

Input/Output

Delay time adjustor for the full-bridge control signal (OUT-C and D)

4

10

DELAY-3

Input/Output

Delay time adjustor for the secondary control signal (OUT-E and F)

5

—

SEC-CONT

Input

Synchronous rectification on/off control

6

—

REMOTE

Input

Remote on/off control

7

11

VREF

Output

5 V/20 mA output

9

12

VCC

Input

IC power supply input

13

13

OUT-F

Output

Secondary control signal

14

14

OUT-E

Output

Secondary control signal

17

15

OUT-D

Output

Full-bridge control signal

18

16

OUT-C

Output

Full-bridge control signal

19

17

OUT-B

Output

Full-bridge control signal

20

18

OUT-A

Output

Full-bridge control signal

22

—

PGND

—

Ground level for the output signal

23

—

SGND

—

Ground level for the small signal

—

19

GND

—

Ground

24

20

RT

Input/Output

Timing resistor for the oscillator

27

1

SYNC

Input/Output

Synchronization I/O for the oscillator

29

2

RAMP-SLP

Input/Output

Ramp sloping adjustor

31

3

RAMP

Input

Ramp waveform set

33

4

CS

Input

Current sense signal input for OCP

34

—

CS-OUT

Output

Current sense information amplifier output

36

5

COMP

Output

Error amplifier output

37

6

FB(–)

Input

Error amplifier negative input

38

7

SS

Output

Timing capacitor for soft start

3, 8,

10 to 12,

15, 16,

21, 25,

26, 28,

30, 32,

35, 39,

40

—

N.C.

—

Open