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AS1331

Datasheet - P i n A s s i g n m e n t s

4 Pin Assignments

Figure 2. Pin Assignments (Top View)

Pin Descriptions

Table 1. Pin Descriptions

Pin

Name

Pin

Number

Description

VOUT

1

Output of the Buck/Boost Converter.

SW1

2

Buck/Boost Switch Pin. Connect the inductor from SW1 to SW2

PGND

3

Power Ground. Both GND pins must be connected.

SW2

4

Buck/Boost Switch Pin. Connect the inductor from SW1 to SW2. An

optional Schottky diode can be connected between this pin and VOUT to

increase efficiency.

VIN

5

Input Supply Pin. A minimum 2.2µF capacitor should be placed between

VIN and GND.

EN

6

Enable Pin. Logic controlled shutdown input.

1 = Normal operation;

0 = Shutdown; quiescent current <1µA.

LBI

7

Low Battery Comperator Input. 1.25V Threshold. May not be left floating.

If connected to GND LBO is working as Output Power okay.

LBO

8

Low Battery Comperator Output. This open-drain output is low when the

voltage on LBI is less than 1.25V.

GND

9

Ground. Both GND pins must be connected.

FB

10

Feedback Pin. Feedback input for the adjustable version. Connect a

resistor divider tap to this pin. The output voltage can be adjusted from 2.5V

NC

11

Exposed Pad. This pad is not connected internally. It can be used for

ground connection between GND and PGND.

AS1331

SW2 2

SW1 4

VOUT 1

PGND 3

LBI

7

LBO

8

GND

9

FB

10

11

VIN 5

EN

6