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

change without notice.

September 2014

DocID026876 Rev 1

1/39

R5973D

Up to 2 A step-down switching regulator for aerospace applications

Datasheet

Features

 General features

– 2 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

35 V

– Low dropout operation: 100% duty cycle

– 250 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

Application

 Dedicated to aerospace and defense

applications

Description

The R5973D is a step-down monolithic power

switching regulator with a minimum switch current

limit of 2.25 A so it is able to deliver up to 2 A DC

current to the load depending on the application

conditions. The output voltage can be set from

1.235 V to 35 V. The high current level is also

achieved thanks to an HSOP8 package with

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

an internal P-channel DMOS transistor (with

to minimize the size of the external components.

An internal oscillator fixes the switching frequency

at 250 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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