ON/OFF

Overcurrent/

Overtemperature

Protection

1.23 V

−

+

BYPASS

LP2985

www.ti.com

SLVS522O – JULY 2004 – REVISED JANUARY 2015

7 Detailed Description

7.1 Overview

The LP2985 family of fixed-output, low-dropout regulators offers exceptional, cost-effective performance for both

portable and nonportable applications. Available in voltages of 1.8 V, 2.5 V, 2.8 V, 2.9 V, 3 V, 3.1 V, 3.3 V, 5 V,

and 10 V, the family has an output tolerance of 1% for the A version (1.5% for the non-A version) and is capable

of delivering 150-mA continuous load current. Standard regulator features, such as overcurrent and

overtemperature protection, are included.

7.2 Functional Block Diagram

7.3 Feature Description

The LP2985 has a host of features that makes the regulator an ideal candidate for a variety of portable

applications:

•

Low dropout: A PNP pass element allows a typical dropout of 280 mV at 150-mA load current and 7 mV at 1-

mA load.

•

Low quiescent current: The use of a vertical PNP process allows for quiescent currents that are considerably

lower than those associated with traditional lateral PNP regulators.

•

Shutdown: A shutdown feature is available, allowing the regulator to consume only 0.01

μA when the

ON/OFF pin is pulled low.

•

Low-ESR-capacitor friendly: The regulator is stable with low-ESR capacitors, allowing the use of small,

inexpensive, ceramic capacitors in cost-sensitive applications.

•

Low noise: A BYPASS pin allows for low-noise operation, with a typical output noise of 30

use of a 10-nF bypass capacitor.

•

Small packaging: For the most space-constrained needs, the regulator is available in the SOT-23 package.

7.4 Device Functional Modes

7.4.1 Normal Operation

In normal operation, the device will output a fixed voltage corresponding with the orderable part number. The

device can deliver 150 mA of continuous load current.

7.4.2 Shutdown Mode

≥40 mV/μs.

Copyright © 2004–2015, Texas Instruments Incorporated

Submit Documentation Feedback

11