New Siliconix Power MOSFETs for Isolated DC/DC Conversion Meet Higher Voltage Demands in Low-Profile PowerPAK™ Package

SANTA CLARA, CALIFORNIA - August 22, 2001 - A new series of higher-voltagen-channel power MOSFETs, the first in the PowerPAK™ SO-8 to be optimized for the primary side of dc-to-dc converters, has been announced by Siliconix incorporated (NASDAQ: SILI), an 80.4%-owned subsidiary of Vishay Intertechnology, Inc. (NYSE: VSH).

These PowerPAK devices feature a thinner profile than the standard SO-8 MOSFETs, as well as superior current and power dissipation capabilities. They will be used in isolated power supply dc-to-dc converters in 24-V to 48-V applications including telecommunications, computer, server, automotive and military aviation products having higher supply voltages. In many applications, they will allow designers to replace DPAK power MOSFET swith a device that is less than half the size.

The new Vishay Siliconix Si7450DP (200 V), Si7846DP (150 V), Si7454DP (100 V), Si7852DP (80 V) and Si7850DP (60 V) can handle currents from 5.3 A up to 12.5 A, enabling higher power density designs. Minimizing switching losses, typical gate charge ratings for the new PowerPAK devices ranges from 18 nC in the 60-V Si7850DP to 34 nC in the 200-V Si7450DP. On-resistance values range from 22 mΩ at a 10-V gate drive in the Si7850DP 60-V device to 80 mΩ at a 10-V gate drive in the 200-V Si7450DP.

Optimized for applications that require minimized conduction losses, the 100-V Si7456DP offers an on-resistance of 25 mΩ at a 10-V gate drive,with low gate charge of 36 nC.

The series features the industry's lowest on-resistance times gate charge product for 60-V to 200-V primary side MOSFETs, which means that less heat is generated due to lower switching and conduction losses, or that higher frequencies may be used, resulting in smaller filter components and a smaller end product. Continuous drain current is improved by at least 13% and maximum power dissipation by at least 26%, while the device profile is decreased by 39%.

Because PowerPAK devices run cooler while producing more power, they can replace a DPAK or two standard SO-8 devices running in parallel, thereby saving space and reducing component costs. The enhanced thermal performance of this new power MOSFET series is made possible through a direct thermalpath from the die to the printed circuit board. Unlike power MOSFETs with an exposed die, PowerPAK's design provides a consistent footprint regardless of the particular silicon used in a given device. This eliminates the need for retooling to accommodate devices with different on-resistance ratings.

Samples and production quantities of the Vishay Siliconix Si7450DP,Si7846DP, Si7456DP, Si7454DP,Si7852DP and Si7850DP are available now, with lead times of four to six 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.

PowerPAK is a trademark of Siliconix incorporated