Preliminary Data

This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to

change without notice.

January 2007

Rev 1

1/47

47

PM6675

High efficiency step-down controller

with embedded 2A LDO regulator

Features switching

– 4.5V to 28V input voltage range

– 0.6V, ±1% voltage reference

– Selectable 1.5V fixed output voltage

– Adjustable 0.6V to 3.3V output voltage

– 1.237V ±1% reference voltage available

– Very fast load transient response using

constant on-time control loop

– Negative current limit

– Latched OVP and UVP

– Soft start internally fixed at 3ms

– Selectable pulse skipping at light load

– Selectable No-Audible (33KHz) pulse skip

mode

– Ceramic output capacitors supported

– Output voltage ripple compensation

– Output soft-end

– Adjustable 0.6V to 3.3V output voltage

– Selectable ±1Apk or ±2Apk current limit

– Dedicated Power-Good signal

– Ceramic output capacitors supported

– Output soft-end

Applications

Description

The PM6675 device consists of a single high

efficiency step-down controller and an

independent Low Drop-Out (LDO) linear

regulator.

The Constant On-Time (COT) architecture

assures fast transient response supporting both

electrolytic and ceramic output capacitors. An

embedded integrator control loop compensates

the DC voltage error due to the output ripple.

A selectable low-consumption mode allows the

highest efficiency over a wide range of load

conditions. The low-noise mode sets the minimum

switching frequency to 33kHz for audio-sensitive

applications.

The LDO linear regulator can sink and source up

to 2Apk. Two fixed current limits (±1A-±2A) can be

chosen.

An active Soft-End is independently performed on

both the switching and the linear regulators

outputs when disabled.

VFQFPN-24 4x4

www.st.com

Order codes

Part number

Package

Packaging

PM6675

VFQFPN-24 4x4 (Exposed Pad)

Tube

Obsolete

Product(s)

- Obsolete

Product(s)

Obsolete

Product(s)

- Obsolete

Product(s)