June 2000

1

MIC5231

MIC5231

Micrel

General Description

The MIC5231

µCap low-dropout voltage regulator is intended

for low-output-current biasing applications. It features ex-

tremely low ground current, not greater than 4

µA under all

load and temperature conditions, making it efficient and ideal

for keep-alive applications in devices such as notebook

computers.

The MIC5231 offers better than 2% initial accuracy and low

dropout (typically 150mV at 10mA output current). An output

capacitor is not required for stable operation, decreasing cost

and board space. Tiny ceramic chip capacitors may be used

to improve transient response.

The MIC5231 also features a control pin which allows the

regulator to be shut down when not required. Its shutdown-

state draws zero current, benefitting battery-powered appli-

cations.

The MIC5231 is available in fixed output voltages of 2.75V,

3.0V, 3.3V and 5V in the small SOT-23-5 IttyBitty™ package.

Contact Micrel for other voltage options.

MICREL INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131 USA

TEL + 1 (408) 944-0800 FAX + 1 (408) 944-0970

Typical Application

IN

EN

OUT

MIC5231-5.0BM5

GND

6V

5V

5V Linear Regulator Application

Ordering Information

Part Number

Marking

Voltage

Temperature Range

Package

MIC5231-2.75BM5

LM2H

2.75V

–40

°C to +125°C

SOT-23-5

MIC5231-3.0BM5

LM30

3.0V

–40

°C to +125°C

SOT-23-5

MIC5231-3.3BM5

LM33

3.3V

–40

°C to +125°C

SOT-23-5

MIC5231-5.0BM5

LM50

5.0V

–40

°C to +125°C

SOT-23-5

Features

• Extremely low quiescent current—

only 0.65

• No output capacitor requirement

• Stable with ceramic or tantalum capacitors

• IttyBitty™ SOT-23-5 surface-mount package

• 10mA output drive

• Low 150mV at 10mA dropout voltage

• Tight load and line regulation

• Low temperature coefficient

• Logic-level enable input

Applications

• Real time clocks

• SRAM backup

• Cellular telephones

• Laptop, notebook and palmtop computers

• Battery-powered equipment

• Bar code scanners

• SMPS post-regulator and dc-to-dc modules

MIC5231

Micropower

Preliminary Information

IttyBitty is a trademark of Micrel, Inc.