May 2014

DocID025489 Rev 1

1/4

For further information contact your local STMicroelectronics sales

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STEVAL-ISA152V1

3.3 V/3 A high efficiency step down DC-DC converter

Data brief

Features

•

3.3 V output voltage

•

3 A DC output current

•

4.5 V to 60 V input voltage

•

500 kHz switching frequency

•

3.5 ms programmed soft-start

•

VBIAS switch-over for improved efficiency at

light load

•

180° out of phase synchronization available

•

Open drain PGOOD available

•

Auto recovery overcurrent and thermal

protection

•

RoHS compliant

Description

The STEVAL-ISA152V1 product evaluation board

is a step-down switching power supply based on

the L7987 regulator in an HTSSOP16 package.

The output voltage can be set starting from 0.8 V.

Low drop-out operation, with almost 100% duty

cycle, can be achieved.

The L7987 is a 61 V, 3 A step-down

asynchronous switching regulator with embedded

power MOSFET caable of delivering up to 3 A of

current, depending on the application conditions.

The embedded switch-over feature on the VBIAS

pin and the light load management (pulse

skipping) are intended to maximize power

conversion efficiency across the entire load

range.

The soft-start, current limit threshold and the

switching frequency are adjustable for application

optimization.

The device includes an internal 250 kHz oscillator

that can be externally adjusted up to 1.5 MHz;

two L7987 regulators can be synchronized in a

180° out-of-phase configuration for reduced total

input RMS current.