Copyright

© ANPEC Electronics Corp.

Rev. A.4 - Jan., 2006

APW7120

www.anpec.com.tw

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ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and advise

customers to obtain the latest version of relevant information to verify before placing orders.

5V to 12V Supply Voltage, 8-PIN, Synchronous Buck PWM Controller

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Operating with Single 5~12V Supply Voltage

or two Supply Voltages

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Drive Dual Low Cost N-Channel MOSFETs

- Adaptive Shoot-Through Protection

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Built-in Feedback Compensation

- Voltage-Mode PWM Control

- 0~100% Duty Ratio

- Fast Transient Response

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±2% 0.8V Reference

- Over Line, Load Regulation and

Operating Temp.

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Programmable Over-Current Protection

- Using R

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Hiccup-Mode Under-Voltage Protection

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118% Over-Voltage Protection

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Adjustable Output Voltage

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Small Converter Size

- 300kHz Constant Switching Frequency

- Small SOP-8 Package

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Built-In Digital Soft-Start

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Shutdown Control using an External MOSFET

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Lead Free Available (RoHS Compliant)

Features

Applications

General Description

The APW7120 is a fixed 300kHz frequency, voltage

mode, synchronous PWM controller. The device drives

two low cost N-channel MOSFETs and is designed to

work with single 5~12V or two supply voltage(s),

providing excellent regulation for load transients.

The APW7120 integrates controls, monitoring and

protection functions into a single 8-pin package to

provide a low cost and perfect power solution.

A power-on-reset (POR) circuit monitors the VCC

supply voltage to prevent wrong logic controls. An

internal 0.8V reference provides low output voltage

down to 0.8V for further applications. An built-in digital

soft-start with fixed soft-start interval prevents the

output voltage from overshoot as well as limiting the

input current. The controller’s over-current protection

monitors the output current by using the voltage drop

across the low-side MOSFET’s R

need of a current sensing resistor. Additional under

voltage and over v oltage protections monitor the

v oltage on FB pin for short-circuit and over-voltage

protections. The over-current protection cycles the

soft-start function until 4 over-current events are

counted.

Pulling and holding the voltage on OCSET pin below

0.15V with an open drain device shuts down the

controller.

Pinouts

1

2

3

4

8

7

6

5

PHASE

OCSET

FB

VCC

BOOT

UGATE

GND

LGATE

SOP-8

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Motherboard

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Graphics Card

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High Current, up to 20A, DC-DC Converters