August 2004

1

M9999-081804

MIC5253

Micrel

MIC5253

100mA Low Noise

General Description

The MIC5253 is an efficient, CMOS voltage regulator opti-

mized for ultra-low-noise applications. It offers 1.5% initial

accuracy, extremely low dropout voltage (165mV at 100mA),

and low ground current (typically 95

µA at full load). The

MIC5253 provides a very low noise output, ideal for RF

applications where a clean voltage source is required. A

noise bypass pin is also available for further reduction of

output noise.

Designed specifically for handheld and battery-powered de-

vices, the MIC5253 provides a TTL-logic-compatible enable

pin. When disabled, power consumption drops nearly to zero.

The MIC5253 also works with low-ESR ceramic capacitors,

reducing the amount of board space necessary for power

applications, critical in handheld wireless devices.

Available in the Teeny™ SC-70-5 package, the MIC5253

offers a wide range of output voltages. Key features include

current limit, thermal shutdown, faster transient response,

and an active clamp to speed up device turn-off.

Typical Application

Ceramic

Ceramic

15

2

3

4

Enable

Shutdown

EN

MIC5253-x.xBC5

EN (pin 3) may be

connected directly

to IN (pin 1).

Ultra-Low-Noise Regulator Application

Features

• Input voltage range: 2.7V to 5.5V

• Teeny™ SC-70-5 package

• Ultra-low output noise: 30

µV(rms)

• 100mA continuous output current, 150mA peak current

• Stability with ceramic output capacitors

• Ultralow dropout: 165mV @ 100mA

• High output accuracy:

1.5% initial accuracy

3.0% over temperature

• Low ground current: 95

µA

• TTL-Logic-controlled enable input

•“Zero” off-mode current

• Thermal shutdown and current limit protection

Applications

• Cellular phones and pagers

• Cellular accessories

• Battery-powered equipment

• Laptop, notebook, and palmtop computers

• Consumer/personal electronics

Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com

Ordering Information

Part Number

Marking

Voltage

Junction Temp. Range*

Package

MIC5253-1.8BC5

LCN

1.8V

–40

°C to +125°C

SC-70-5

MIC5253-1.85BC5

L71J

1.85V

–40

°C to +125°C

SC-70-5

MIC5253-2.6BC5

LCP

2.6V

–40

°C to +125°C

SC-70-5

MIC5253-2.9BC5

L729

2.9V

–40

°C to +125°C

SC-70-5

MIC5253-3.0BC5

LCG

3.0V

–40

°C to +125°C

SC-70-5

MIC5253-3.3BC5

L733

3.3V

–40

°C to +125°C

SC-70-5

Other voltages available. Contact Micrel for details.

Teeny is a trademark of Micrel, Inc.