The AAT1265 step-up converter from Advanced Analogic Technologies can supply either 100 mA to a 3.3-V load from a single AA cell or 250 mA from two AA cells. Employing synchronous, fixed-frequency operation, the chip also delivers efficiency up to 93% and True Load Disconnect in an extremely small footprint.
Boost converters typically present an unwanted conduction path from the input to the output via the body diode of the P-channel MOSFET when the system is not active. However, in the AAT1265, the True Load Disconnect feature disconnects the body diode from the output. This function eliminates the need for an external load switch and control circuitry.
The AAT1265 is available in a 2.0-mm x 2.1-mm SC70JW-8 package. The device sells for $0.81 in 1000-piece quantities.