Si9140

Siliconix' Si9140 Buck converter IC is a high-performance, surface-mount switchmode controller made to power the new generation of low-voltage, high-performance microprocessors.

The Si9140 has an input voltage range of 3 to 6.5 V to simplify power supply designs in desktop PCs. Its high-frequency switching capability and wide bandwidth feedback loop provide tight, absolute static and transient load regulation. Circuits using the Si9140 can be implemented with low-profile, inexpensive inductors, and will dramatically minimize power supply output and processor decoupling capacitance. The Si9140 is designed to meet the stringent regulation requirements of new and future high-frequency microprocessors, while improving the overall efficiency in new "green" systems.

Today's state-of-the-art microprocessors run at frequencies over 100 MHz. Processor clock speeds are going up and so are current requirements, but operating voltages are going down. These simultaneous changes have made dedicated, high-frequency, point-of-use buck converters an essential part of any system design. These point-of-use converters must operate at higher frequencies and provide wider feedback bandwidths than existing converters, which typically operate at less than 250 kHz and have feedback bandwidths of less than 50 kHz. The Si9140's 100-kHz feedback loop bandwidth ensures a minimum improvement of one-half the required output/decoupling capacitance, resulting in a tremendous reduction in board size and cost of implementation.

With the microprocessing power of any PC representing an investment of hundreds of dollars, designers need to ensure that the reliable operation of the processor will not be affected by the power supply. The Si9140 provides this assurance. A demo board, the Si9140DB, is available.