Conceptual

CS902-A-R

www.richtek.com

June 13, 2013

2

Pin Assignment

Pin Number

Pin Name

Pin Function

1,2

VINB1

Power input voltage pins for the VI/O buck converter. VINB1 is

internally connected to VINB3.

22,24,27

NC

Not connected. Should be floating or connected to GND

3

AVIN

Analog input voltage of the device. This is the input for the analog

circuits. Connect this pin with a decoupling capacitor.

4

AGND

Analog ground.

5

SDA

I

2C compatible serial-data input/output.

6

SCL

I

2C compatible serial-clock input.

7

A0

I

2C compatible device address bit 0.

8

HVS

Boost HVS enable.

9

NC

Not connected. Should be floating.

10

COMP

Compensation pin for the boost converter.

11

VL

Internal logic regulator output. Connect this pin with a decoupling

capacitor.

12

NTC

Temperature compensation pin for VGH.

13,14

PGND

Power ground.

15,16

LX

Switch pins of the boost converter.

17

LXI

High side switch input pin.

18,19

LXO

High side switch output pin. Also used for feedback of the boost

converter

20

VGL

Output sensing pin of the VGL negative charge pump.

21

DRVN

Base drive of the external NPN transistor for the VGL negative charge

pump.

23

DRVP

Base drive of the external PNP transistor for the VGH positive

charge pump.

25

A1

I

2C compatible device address bit 1.

26

VFLK

Gate Shaping Control Input. When VFLK is high, the switch between

VGH and VGHM is on and the switch between VGHM and RE is off.

When VFLK is low, the switch between VGH and VGHM is off and the

switch between VGHM and RE is on.

28

OGND

GND of OPAMP.

29

OP_OUT

OUTPUT of OPAMP.

30

NEG

Negative Input of OPAMP

31

POS

Positive Input of OPAMP