AP2004

PWM Buck Controller

This datasheet contains new product information. Anachip Corp. reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of

this product. No rights under any patent accompany the sale of the product.

Rev. 0.4 Arpr 6, 2004

1/8

Features

- PWM Buck Control Circuitry

- Operating voltage can be up to 27V

- Under voltage Lockout (UVLO) Protection

- Short Circuit Protection (SCP)

- Soft-start circuit

- Variable Oscillator Frequency -- 300Khz Max

- 1.25V voltage reference Output

- 8-pin PDIP and SOP packages

Applications

- Backlight inverter

- LCD Monitor

- XDROM, XDSL Product

- DC/DC converters in computers, etc.

General Description

The AP2004 integrates Pulse-Width-Modulation

(PWM) control circuit into a single chip, mainly

designs for power-supply regulator. All the functions

include an on-chip 1.25V reference output, an error

amplifier, an adjustable oscillator, a soft-start,

UVLO, SCP circuitry, and a push-pull output circuit.

Switching frequency is adjustable by trimming CT.

During low VCC situation, the UVLO makes sure

that the outputs are off until the internal circuit

operates normally.

Pin Assignment

1

2

3

8

7

6

5

4

OUT

GND

SCP

SS

FB

VCC

CT

COMP

( Top View )

PDIP/SOP

Pin Descriptions

Name

Description

CT

Timing Capacitor

FB

Voltage Feedback

SS

Soft-Start.

COMP

Feedback Loop Compensation

OUT

PWM Output

GND

Ground

VCC

Supply Voltage

SCP

Short Circuit Protection

Ordering Information

AP2004 X X X

Package

Packing

S: SOP-8L

Blank : Tube

A : Taping

Lead Free

Blank : Normal

L : Lead Free Package

N: PDIP-8L