MP8802 – LOW DROPOUT, 250mA LINEAR REGULATOR

MP8802 Rev. 1.3

www.MonolithicPower.com

4

3/6/2006

MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.

© 2006 MPS. All Rights Reserved.

PIN FUNCTIONS

Pin #

Name

Description

1

IN

Power Source Input. IN supplies the internal power to the MP8802 and is the source of the

pass transistor. Bypass IN to GND with a 1µF or greater capacitor.

2

GND

Ground.

3

EN

Enable Input. Drive EN high to turn on the MP8802, drive EN low to turn it off. For

automatic startup, connect EN to IN.

4

FB

Feedback Input. Connect a resistive voltage divider from OUT to FB to set the output

voltage. OUT feedback threshold is 1.222V.

5

OUT

Regulator Output. OUT is the output of the linear regulator. Bypass OUT to GND with a

1µF or greater capacitor.

OPERATION

The MP8802 is a low-current, low-noise,

high-PSRR, low-dropout, linear regulator. It is

intended for use in devices that require very low

noise power supplies and high-PSRR such as

PLL VCO supplies for mobile handsets and

802.11 PC Cards, as well as audio codecs and

microphones. The MP8802 uses a PMOS pass

element and features internal thermal shutdown.

As shown in Figures 1 and 2, optional feed-

FB and OUT pins for an improved transient

response.

MP8802_F01_BD01

GND

FB

OUT

--

+

BANDGAP

REFERENCE

INTERNAL

RESISTOR

DIVIDER

Figure 1—Ultra-Low-Noise Fixed Output Regulator

MP8802_F02_BD02

R1

R2

--

+

BANDGAP

REFERENCE

GND

FB

OUT

EXTERNAL

RESISTOR

DIVIDER