CS51221

http://onsemi.com

6

PACKAGE PIN DESCRIPTION

Package

Pin #

Pin

Symbol

Function

1

GATE

External power switch driver with 1.0 A peak capability. Rail to rail output occurs when the capacitive load is

between 470 pF and 10 nF.

2

Current sense comparator input.

3

SYNC

Bidirectional synchronization. Locks to highest frequency.

4

FF

PWM ramp.

5

UV

Undervoltage protection monitor.

6

OV

Overvoltage protection monitor.

7

8

Voltage at this pin sets pulse−by−pulse overcurrent threshold.

9

Feedback voltage input. Connected to the error amplifier inverting input.

10

COMP

Error amplifier output.

11

SS

Charging external capacitor restricts error amplifier output voltage during the power up or fault conditions.

12

LGND

Logic ground.

13

3.3 V reference voltage output. Decoupling capacitor can be selected from 0.01

mF to 10 mF.

14

Logic supply voltage.

15

PGND

Output power stage ground.

16

Output power stage supply voltage.