Plessey Semiconductors Ltd, Tamerton Road, Roborough, Plymouth, UK PL6 7BQ

Data Sheet 292203 issue 1

Tel: +44 (0)1752 693000

Fax: +44 (0)1752 693200

1

PS22921

12V, 500mA Fast Transient Response Linear Regulator

Preliminary

Data Sheet 292203 issue 1 Mar-13

Typical Application

Description

The PS22921 is a high performance, precision linear regulator

with very low dropout voltage and excellent transient response.

It is designed to operate with wide input voltage range of 1.7 –

12 Volts making it ideal for two step conversion. The device is

capable of supplying 500mA of output current with a typical

dropout voltage of 300mV. The output Voltage is available in

either fixed or adjustable options. For fixed option, the internal

resistor network can be set in 100mV increment ranging from

0.5 to 5.0 volts.

The product includes an Enable pin for electrical on/off of the

regulator. Forcing the Enable pin to logic low shuts down the

LDO and reduces the supply current below 1µA. The PS22921

features fast transient response and low self output noise.

Connecting a capacitor form ByPass to GND further enhances

the PSRR and the output noise.

An open collector power good flag with 500µs delay is available

for systems requiring supply monitoring and sequencing of

other supplies. The regulator features the full suite of protection

with a combination of current limit and thermal overload

protection.

to +125°C junction temperature range.

Features

•

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Fixed and adjustable output voltage

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500mA maximum output current

•

300mV typical dropout voltage

•

Bypass output for low PSRR and output noise

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Power Good pin with 500µs delay

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Low self noise

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Shutdown mode for longer battery life

•

High PSRR typically 60dB at 100Hz

•

Stable with a wide range of Ceramic, Tantalum

or Electrolytic capacitors

•

Current limit protection

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Thermal Shutdown

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-40°C to 125°C temperature range

•

Available in SOT23-5

Applications

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Set Top Boxes

•

Digital Audio systems

•

DSP

•

POL regulators

•

SMPS post regulator

Vin = 1.7 – 12v