Copyright

© ANPEC Electronics Corp.

Rev. A.3- Sep., 2008

APW7145

www.anpec.com.tw

1

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.

3A, 12V, Synchronous-Rectified Buck Converter

The APW7145 is a 3A synchronous-rectified Buck con-

verter with integrated 55m

Ω power MOSFETs. The

APW7145, designed with a current-mode control scheme,

can convert wide input voltage of 4.3V to 14V to the out-

put voltage adjustable from 0.8V to VIN to provide excel-

lent output voltage regulation.

For high efficiency over all load current range, the

APW7145 is equipped with an automatic Skip/PWM mode

operation. At light load, the IC operates in the Skip mode,

which keeps a constant minimum inductor peak current,

to reduce switching losses. At heavy load, the IC works in

PWM mode, which inductor peak current is programmed

by the COMP voltage, to provide high efficiency and ex-

cellent output voltage regulation.

The APW7145 is also equipped with power-on-reset, soft-

start, soft-stop, and whole protections (under-voltage,

over-voltage, over-temperature, and current-limit) into a

single package. In shutdown mode, the supply current

drops below 3

µA.

This device, available SOP-8P and DFN4x4-8 packages,

provides a very compact system solution with minimal

external components and PCB area.

Features

General Description

•

Wide Input Voltage from 4.3V to 14V

•

Output Current up to 3A

•

Adjustable Output Voltage from 0.8V to V

IN

- ±2% System Accuracy

•

55m

Ω Integrated Power MOSFETs

•

High Efficiency up to 95%

- Automatic Skip/PWM Mode Operation

•

Current-Mode Operation

- Easy Feedback Compensation

- Stable with Low ESR Output Capacitors

- Fast Load/Line Transient Response

•

Power-On-Reset Monitoring

•

Fixed 500kHz Switching Frequency in PWM Mode

•

Built-in Digital Soft-Start and Soft-Stop

•

Current-Limit Protection with Frequency Foldback

•

118% Over-Voltage Protection

•

Hiccup-Mode 50% Under-Voltage Protection

•

Over-Temperature Protection

•

<3

µA Quiescent Current in Shutdown Mode

•

SOP-8P and Compact 4mmx4mm DFN-8

(DFN4x4-8) Packages

•

Lead Free and Green Devices Available

(RoHS Compliant)

Applications

•

OLPC, UMPC

•

Notebook Computer

•

Handheld Portable Device

•

Step-Down Converters Requiring High Efficiency

and 3A Output Current

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