Buck-Boost Controller Chip Delivers High Efficiencies

The Si9165BQ controller IC delivers dc-to-dc conversion efficiencies of up to 95% in cell phones and other mobile communication devices. The chip makes possible a complete converter in an area of just 32 mm x 19 mm. It combines conversion circuitry with on-board n- and p-channel MOSFETs in a TSSOP-20 package.The chip's input range is from 2.7V to 6V, and it can be programmed to function either as a synchronous buck or as a boost converter. It can step voltages down to 1.3V or up to 6V. Output current is up to 600 mA at 3.3V. In addition, the IC operates at frequencies up to 2 MHz, enabling designers to use smaller magnetics. Also available is the Si9166BQ, which omits the MOSFETs.