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BYPASS

LP3981

2.2 µF

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2.2 µF

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Design

LP3981

SNVS159H – OCTOBER 2001 – REVISED JULY 2015

LP3981 Micropower, 300-mA Ultra-Low-Dropout CMOS Voltage Regulator

1 Features

3 Description

Performance of the LP3981 device is optimized for

1

•

2.5-V to 6-V Input Range

battery-powered systems to deliver ultra-low-noise,

•

300-mA Output Current

extremely low dropout voltage, and low quiescent

•

60-dB PSRR at 1 kHz

current. Regulator ground current increases only

slightly in dropout, further prolonging the battery life.

•

≤ 1-μA Quiescent Current When Shut Down

•

Fast Turnon Time: 120

μs (typical) with CBYPASS =

Power supply rejection is better than 60 dB at low

0.01 µF

frequencies. This high power supply rejection is

maintained down to lower input voltage levels

•

132-mV Typical Dropout with 300-mA Load

common to battery-operated circuits.

•

35-

μVrms Output Noise Over 10 Hz to 100 kHz

The device is ideal for mobile phone and similar

•

Logic Controlled Enable

battery-powered wireless applications. It provides up

•

Stable With Ceramic and High-Quality Tantalum

to 300 mA, from a 2.5-V to 6-V input, consuming less

Capacitors

than 1 µA in disable mode.

•

Thermal Shutdown and Short-Circuit Current Limit

The LP3981 is available in 8-pin VSSOP-8 and 6-pin

•

Low Thermal Resistance in WSON-6 Package

WSON packages. Performance is specified for

−40°C

Gives Excellent Power Capability

to +125°C temperature range. The device available in

the following output voltages: 2.5 V, 2.7 V, 2.8 V,

2.83 V, 3 V, 3.03 V and 3.3 V as standard. Other

2 Applications

output options can be made available; contact your

•

CDMA Cellular Handsets

local TI sales office for more information.

•

Wideband CDMA Cellular Handsets

Device Information(1)

•

GSM Cellular Handsets

PART NUMBER

PACKAGE

BODY SIZE (NOM)

•

Portable Information Appliances

WSON (6)

4.00 mm x 3.00 mm

LP3981

VSSOP (8)

3.00 mm x 3.00 mm

(1) For all available packages, see the orderable addendum at

the end of the data sheet.

Typical Application Circuit

Note: Pin numbers in parenthesis indicate WSON package.

1

An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. PRODUCTION DATA.