New Multi-Output, Sequence-Selectable Power-Supply Controller Converts Power Efficiently, Prolongs Battery Life in Mobile Products

SANTA CLARA, CALIFORNIA - March 1, 2002 - Siliconix incorporated (NASDAQ: SILI), an 80.4%-owned subsidiary of Vishay Intertechnology (NYSE: VSH), today announced the release of a multi-output, sequence-selectable power-supply controller intended for mobile computing and communications applications. With up to 95% conversion efficiency achieved with synchronous rectification, the new low-noise Si9137 dc-to-dc controller helps to maximize battery life in portable products, including notebook and subnotebook computers, PDAs, mobile communicators, and portable displays.

The highly efficient Si9137 features fixed 3.3-V and 5-V outputs and a 500-mA adjustable 5-V to 12-V output set by an external resistor divider. Additional features include programmable output sequencing, a 3.3-V reference for precision analog circuits, a 5-V/30-mA linear regulator output for MOSFET gate voltage control, and output current limit and over/under voltage protection.

To minimize power consumption, the Si9137 operates in power-saving pulse skipping mode (PSM) at light loads. Operational frequency is fixed at a 300 kHz to reduce noise and output voltage regulation is ±3% over the combined line voltage, load current, and temperature extremes.

A wide input voltage range of 5.5 V to 30 V gives designers a flexible power-supply conversion solution requiring minimal external control components. The Si9137 provides selectable pre-programmed power-up sequencing, power-good signal with delay, internal frequency compensation networks, and automatic boot-strapping. Just three inductors are needed for a complete 75-W power conversion solution based on the Si9137, eliminating the need for a transformer.

The Si9137 is available in the 28-pin SSOP package and specified to operate over the extended commercial temperature range of 0°C to 90°C.

Samples and production quantities of the Si9137 are available now, with lead times of eight weeks for larger orders.

Vishay Intertechnology, Inc., a Fortune 1,000 Company listed on the NYSE (VSH), is one of the world's largest manufacturers of discrete semiconductors (diodes, rectifiers, transistors, and optoelectronics and selected ICs) and passive electronic components (resistors, capacitors, inductors, sensors, and transducers). These components are used in virtually all types of electronic devices and equipment, in the industrial, computing, automotive, consumer, telecommunications, military, aerospace, and medical markets. Its product innovations, successful acquisition strategy, and ability to provide "one-stop shop" service have made Vishay a global industry leader. Vishay can be found on the Internet at http://www.vishay.com.