400mA Micropower Synchronous Step-Up DC/DC Converter with Output Disconnect

The LTC3525L-3 is a high efficiency synchronous step-up DC/DC converter with output disconnect that can start up with an input as low as 0.7V. It offers a compact, high efficiency alternative to charge pumps in single cell or dual cell alkaline applications. Only three small external components are required. The LTC3525L-3 generates a fixed 3V output voltage.

The device includes a 0.5Ω N-channel MOSFET switch and a 0.85Ω P-channel synchronous rectifier. Peak switch current ranges from 150mA to 400mA, depending on load, providing enhanced efficiency. Quiescent current is an ultralow 7μA, maximizing battery life in portable applications.

Other features include <1μA shutdown current, anti-ringing control and thermal shutdown. The LTC3525L-3 is available in a tiny 6-pin SC70 package.

Vout

Min Startup Voltage

Features

LTC3525-3/3.3/5

3V/3.3V/5V

1V

Output Disconnect

LTC3525D-3.3

3.3V

0.85V

Pass Through Mode

LTC3525L-3

3V

0.85V

Output Disconnect

Applications

* MP3 Players

* Portable Instruments

* Glucose Meters

* Digital Cameras

* Start-Up at 0.7V Typical, 0.88V Guaranteed

* Up to 95% Efficiency

* Output Disconnect and Inrush Current Limit

* 3V Fixed Output Voltage

* Delivers 65mA at 3V from a 1V Input or 160mA from a 1.8V Input

* Burst Mode® Operation: IQ = 7μA

* VIN: 0.5V to 4.5V