Preliminary Datasheet

LP3321

LP3321 – 01 Vesion 1.1 Datasheet

Feb.-2011

www.lowpowersemi.com

Page 2 of 9

Functional pin description

TSOT-23-5

TSOT-23-6

Pin Name

Pin Function

1

1

SW

Switch Pin. Connect this Pin to inductor and catch diode. Minimize the track

area to reduce EMI.

2

2

GND

Ground Pin

3

3

FB

Feedback Reference Voltage Pin. Series connect a resistor between WLED

and ground as a current sense. Sense the current feedback voltage to set the

current rating.

4

4

EN

Chip Enable (Active High). Voltage sensing input to trigger the function of

over voltage protection. Note that this pin is high impedance. There should

be a pull low 100kΩ resistor connected to GND when the control signal is

floating.

5

NC

No connected.

5

6

Vin

Supply Input Voltage Pin. Bypass 1uF capacitor to GND to reduce the input

noise.

Function Block Diagram