January 2002

1

MIC5239

MIC5239

Micrel

MIC5239

Low Quiescent Current 500mA

Advance Information

General Description

The MIC5239 is a low quiescent current,

µCap low-dropout

regulator. With a maximum operating input voltage of 30V

and a quiescent current of 23

µA, it is ideal for supplying keep-

alive power in systems with high-voltage batteries.

Capable of 500mA output, the MIC5239 has a dropout

voltage of only 350mV. It can provide high output current for

applications such as USB.

As a

µCap LDO, the MIC5239 is stable with either a ceramic

or a tantalum output capacitor. It only requires a 3.3

µF output

capacitor for stability.

The MIC5239 includes a logic compatible enable input and an

undervoltage error flag indicator. Other features of the

MIC5239 include thermal shutdown, current-limit, overvolt-

age shutdown, load-dump protection, reverse leakage pro-

tections, and reverse battery protection.

Available in the thermally enhanced SOIC-8, MSOP-8 and

SOT-223, the MIC5239 comes in fixed 3.0V and adjustable

voltages. For other output voltages, contact Micrel.

Typical Application

3.0V/100

µA

30V

IN

MIC5239

EN

OUT

GND

FLG

Regulator with Low I

Features

• Ultra-low quiescent current (I

• Continuious 500mA output current

• Wide input range: 2.3V to 30V

• Low dropout voltage:

350mV @500mA;

•

±1.0% initial output accuracy

• Stable with ceramic or tantalum output capacitor

• Logic compatible enable input

• Low output voltage error flag indicator

• Overcurrent protection

• Thermal shutdown

• Reverse-leakage protection

• Reverse-battery protection

• High-power SOIC-8, MSOP-8 and SOT-223 packages

Applications

• USB power supply

• Keep-alive supply in notebook and portable personal

computers

• Logic supply from high-voltage batteries

• Automotive electronics

• Battery-powered systems

Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com

Ground Current vs. Input Voltage

10

15

20

25

30

35

40

4

9

14

19

24

29

INPUT VOLTAGE (V)

I

I

I