Current

Limit

IN

OUT

EN

Control

EN

Output

Discharge

140-µs

DELAY

PG

GND

3 M

RAD

100

Copyright © 2016, Texas Instruments Incorporated

EA

VIN

+

±

VBG

45 k

17

LP5912

www.ti.com

SNVSA77D – DECEMBER 2015 – REVISED NOVEMBER 2016

Product Folder Links: LP5912

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Copyright © 2015–2016, Texas Instruments Incorporated

8 Detailed Description

8.1 Overview

The LP5912 is a low-noise, high PSRR, LDO capable of sourcing a 500-mA load. The LP5912 can operate down

to 1.6-V input voltage and 0.8-V output voltage. This combination of low noise, high PSRR, and low output

voltage makes the device an ideal low dropout (LDO) regulator to power a multitude of loads from noise-sensitive

communication components to battery-powered system.

The LP5912 Functional Block Diagram contains several features, including:

•

Internal output resistor divider feedback;

•

Small size and low-noise internal protection circuit current limit;

•

Reverse current protection;

•

Current limit and in-rush current protection;

•

Thermal shutdown;

•

Output auto discharge for fast turnoff; and

•

Power-good output, with fixed 140-µs typical delay.

8.2 Functional Block Diagram

8.3 Feature Description

8.3.1 Enable (EN)

The LP5912 EN pin is internally held low by a 3-M

Ω resistor to GND. The EN pin voltage must be higher than the

VEN(ON) threshold to ensure that the device is fully enabled under all operating conditions. The EN pin voltage

must be lower than the VEN(OFF) threshold to ensure that the device is fully disabled and the automatic output

discharge is activated.

When the device is disabled the output stage is disabled, the PG output pin is low, and the output automatic

discharge is ON.