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

change without notice.

October 2014

DocID027027 Rev 1

1/38

R5973AD

Up to 1.5 A step-down switching regulator for aerospace

applications

Datasheet

Features

 General features

– 1.5 A DC output current

– Operating input voltage from 4 V to 36 V

– 3.3 V / (± 2%) reference voltage

– Large ambient temperature range:

-40 °C to 125 °C

– Output voltage adjustable from 1.235 V to

– Low dropout operation: 100% duty cycle

– 500 kHz internally fixed frequency

– Voltage feed-forward

– Zero load current operation

– Internal current limiting

– Inhibit for zero current consumption

– Synchronization

– Protection against feedback disconnection

– Thermal shutdown

 Aerospace and defense features

– Suitable for use in aerospace and defense

applications

– Dedicated traceability and part marking

– Production parts approval documents

available

– Adapted extended life time and

obsolescence management

– Extended product change notification

process

– Designed and manufactured to meet sub-

ppm quality goals

– Advanced mold and frame designs for

superior resilience in harsh environments

(acceleration, EMI, thermal, humidity)

– Extended screening capability on request

Applications

 Dedicated to aerospace applications

Description

The R5973AD is a step-down monolithic power

switching regulator with a minimum switch current

limit of 1.8 A, so it is able to deliver up to 1.5 A DC

current to the load depending on the application

conditions. The output voltage can be set from

achieved thanks to an HSOP8 package with an

down to approximately 40 °C/W. The device uses

an internal P-channel DMOS transistor (with

element to minimize the size of the external

components. An internal oscillator fixes the

switching frequency at 500 kHz. The large

ambient temperature range makes it ideal for

aerospace and defense applications. A pulse-by-

pulse current limit with the internal frequency

modulation offers an effective constant current

short-circuit protection.

HSOP8 - exposed pad

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