Description

The PM6675S 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 33 kHz for audio-sensitive applications.

The LDO linear regulator can sink and source up to 2 Apk. Two fixed current limits (±1 A-±2 A) can be chosen.

An active soft-end is independently performed on both the switching and the linear regulators outputs when disabled.

Features

■ Switching section

– 4.5 V to 28 V input voltage range

– 0.6 V, ±1 voltage reference

– Selectable 1.5 V fixed output voltage

– Adjustable 0.6 V to 3.3 V output voltage

– 1.237 V ±1 reference voltage available

– Very fast load transient response using constant on-time control loop

– No RSENSE current sensing using low side MOSFETs RDS(ON)

– Negative current limit

– Latched OVP and UVP

– Soft-start internally fixed at 3 ms

– Selectable pulse skipping at light load

– Selectable No-Audible (33 kHz) pulse skip mode

– Ceramic output capacitors supported

– Output voltage ripple compensation

– Output soft-end

■ LDO regulator section

– Adjustable 0.6 V to 3.3 V output voltage

– Selectable ±1 Apk or ±2 Apk current limit

– Dedicated power-good signal

– Ceramic output capacitors supported

– Output soft-end

Applications

■ Notebook computers

■ Graphic cards

■ Embedded computers