The LP3981 is designed for portable RF and wireless applications demanding performance and space requirements. The LP3981 performance is optimized for battery-powered systems to deliver ultra low noise and low quiescent current. Regulator ground current increases only slightly in dropout, further prolonging the battery life. The LP3981 also works with low-ESR ceramic capacitors, reducing the amount of board space necessary for power applications, critical in hand-held wireless devices. The LP3981 consumes less than 0.01μA in shutdown mode and has fast turn-on time less than 50μs. The other features include ultra low dropout voltage, high output accuracy, current limiting protection, and high ripple rejection ratio. It is available in the 5-lead of SOT23-5 packages.

Applications
 

Portable Media Players/MP3 players

Cellular and Smart mobile phone

LCD

DSC Sensor

Wireless Card

Features
 

Ultra-Low-Noise for RF Application

2V- 6.5V Input Voltage Range

Low Dropout : 220mV @ 300mA

1.2V, 1.5V, 1.8V, 2.5V, 2.8V 3.0V and 3.3V Fixed

300mA Output Current, 550mA Peak Current

High PSSR:-76dB at 1KHz

< 0.01uA Standby Current When Shutdown

Available in SOT23-5 Package

TTL-Logic-Controlled Shutdown Input

Ultra-Fast Response in Line/Load transient

Current Limiting and Thermal Shutdown Protection

Quick start-up (typically 50uS)