Copyright

© ANPEC Electronics Corp.

Rev. A.2 - Jan., 2008

APW7136A/B/C

www.anpec.com.tw

7

Pin Descriptions

Pin No.

Name

Function Description

1

LX

Switch pin. Connect this pin to inductor/diode here.

2

GND

Power and signal ground pin.

3

FB

Feedback Pin. Reference voltage is 0.25V. Connect this pin to cathode of the lowest LED and

4

EN

Enable Control Input. Forcing this pin above 1.0V enables the device, or forcing this pin below 0.4V

to shut it down. In shutdown, all functions are disabled to decrease the supply current below 1

µA.

Do not leave this pin floating.

5

OVP

Over Voltage Protection Input Pin. OVP is connected to the output capacitor of the converter.

6

VIN

Main Supply Pin. Must be closely decoupled to GND with a 4.7

µF or greater ceramic capacitor.

Block Diagram

UVLO

Oscillator

Control Logic

Σ

VIN

EN

FB

GND

LX

OVP

Over-

Temperature

Protection

V

REF

0.25V

EAMP

COMP

ICMP

Slope

Compensation

Gate Driver

Current Sense

Amplifier

Error

Amplifier

Current

limit

Soft-

start