Pin Description

Pin

Name

Function

1

COMP

Compensation network connection. Connected to the output of the voltage error amplifier.

The RC compenstion network should be connected from this pin to AGND. An additional

100pF high frequency capacitor to AGND is recommended.

2

FB

Output voltage feedback input.

3

SHDN

Shutdown control input, Open = enable, Ground = disable.

4

AGND

Analog ground, connect directly to PGND.

5

PGND

Power ground.

6

PGND

Power ground.

7

PGND

Power ground.

8

PGND

Power ground.

9

SW

Power switch input. Switch connected between SW pins and PGND pins

10

SW

Power switch input. Switch connected between SW pins and PGND pins

11

SW

Power switch input. Switch connected between SW pins and PGND pins

12

BYP

Bypass-Decouple Capacitor Connection, 0.1µF ceramic capacitor recommended.

13

V

IN

Analog power input. A small RC filter is recommended, to suppress line glitches. Typical

values of 10

Ω and ≥ 0.1µF are recommended.

14

SS

Softstart Input. External capacitor and internal current source sets the softstart time.

15

FS

Switching frequency select input. Open = F

16

TEST

Factory test pin, connect to ground.

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