Siliconix Intros DC/DC Step-Down Converters

Siliconix Inc. (Santa Clara, CA), a subsidiary of Vishay Intertechnology Inc. (Malvern, PA), announced three new 600mA, synchronous-buck, converter ICs that will help to prolong the run-times provided by single-cell, lithium-ion batteries. The Si9174, Si9175 and Si9176 step-down converter ICs, which combine specifications for low output voltage and high switching frequency with small solution footprints, are intended for end products, including cell phones, PDAs, digital cameras, MP3 players, portable scanners, LCD modules and dc/dc converter modules.

The three devices convert 2.6V to 6V input voltages to output voltages as low as 0.4V. A maximum pulse-width modulation switching frequency for the Si9174, Si9175 and Si9176 of 2MHz reduces output capacitor and inductor size. With integrated power MOSFETs and only six external components - one inductor, three capacitors and two resistors - the Si9174, Si9175 and Si9176 allow manufacturers to cut component and assembly costs, in addition to enabling design of more compact and efficient electronic systems.

The Si9174 features a DAC input for fast dynamic output-voltage adjustments from 0.4V up to the input voltage, while the Si9175 and Si9176 feature a fixed output voltage down to 1.2V set by external resistors. Integrated protection features include thermal shutdown, under-voltage lockout and over-current protection. The three converters are rated for operation over the industrial temperature range of -40 to +85 degrees C, and are available in an MSOP-10 package or a lead-less MLP33 package measuring 3mm x 3mm.

Samples and production quantities of the Si9174, Si9175 and Si9176 are available now with lead times of six to eight weeks for larger orders. Pricing for US delivery in 50,000-piece quantities starts at $1.30.