This is information on a product in full production.

November 2014

DocID10992 Rev 7

1/16

ST1S03

1.5 A, 1.5 MHz adjustable, step-down switching regulator

Datasheet

- production data

Features

 Step-down current mode PWM (1.5 MHz)

DC-DC converter

 2% DC output voltage tolerance

 Internal soft-start for STARTUP current

limitation and power on delay of 50 - 100 µs

 Typical efficiency: > 70% over all operating

conditions

 1.5 A output current capability

 Not switching quiescent current: max 2.5 mA

over temperature range

 Switch VDS: max. 350 mV at ISW = 750 mA

 Uses tiny capacitors and inductors

 Available in DFN6D 3 x 3 mm package with

exposed pad

Description

The ST1S03 is a step-down DC-DC converter

optimized for powering a low voltage digital core

in HDD applications and, generally, to replace the

high current linear solution when the power

dissipation may cause a high heating of the

application environment. It provides up to 1.5 A

over an input voltage range of 3 V to 16 V. A high

switching frequency (1.5 MHz) allows the use of

tiny surface-mount components: as well as the

resistor divider to set the output voltage value,

only an inductor, a Schottky diode and two

capacitors are required. Besides, a low output

ripple is guaranteed by the current mode PWM

topology and by the use of low ESR SMD ceramic

capacitors. The device is thermal protected and

current limited to prevent damages due to an

accidental short-circuit. The ST1S03 device is

available in a DFN6D package.

DFN6D (3 x 3 mm)

Table 1. Device summary

Order code

Package

Packaging

ST1S03PUR

DFN6D (3 x 3 mm)

Tape and reel

www.st.com