Linear Technology Corp. (LTC, Milpitas, CA) introduced two new dc/dc converters to power Intel's Centrino® mobile technology for thin and light notebook PCs. The LTC3734 and LTC3735 are high-efficiency, synchronous step-down, dc/dc controllers with integrated MOSFET drivers and Intel® Pentium® M-compatible, power-saving mode. The LTC3734 and LTC3735 can be used to power Pentium M processors in single-board computers, servers with multiple racks, networking servers and communication systems.
The ICs operate from input supplies ranging from 4V to 30V, and offer a ±1% accurate 0.6V reference voltage; a 210kHz to 550kHz adjustable operating frequency; on-board MOSFET drivers; current-mode operation; over-voltage protection; a short-circuit shutdown timer that can also be disabled; cycle-by-cycle current limiting; and a sense resistor to accurately size the MOSFETs, inductor and output capacitors. Depending on the microprocessor speed and the CPU's maximum current requirement, designers can choose either the single-phase LTC3734 for up to 20A, or the PolyPhase® LTC3735 for up to 40A load current capability.
The LTC3734 is housed in a 5mm x 5mm QFN package, and the two-phase LTC3735 is offered in a 36-lead SSOP. The LTC3734 is priced at $3.05 each and the LTC3735 at $4.45 each for 1,000-piece quantities.
