El SEGUNDO, CA. April 2000 - International Rectifier (IR^®), the power conversion experts, have expanded their offering of application- specific HEXFET^® power MOSFETs for DC-DC conversion applications, adding more than 40 devices for use in isolated converters ranging from sub-2V to 5V to its industry-leading product line. These new primary- and secondary-side MOSFETs bring efficiency improvements of up to 4 percent for a range of circuit topologies without further design changes. These topologies include active and passive reset and two transistor forward systems, as well as bridge and two-stage converters.

IR's new primary-side HEXFET^® power MOSFETs are optimized for fast switching with good R_DS(on) and very low gate charge, and feature VGS ratings of 30V on all products. In general, these devices are aimed at converters with 24V or 48V inputs and ratings of greater than 10W. A range of package options is provided to match current handling requirements, including D-Pak, I-Pak, TO-220, D2Pak and TO-262 styles. Additionally, in early Summer 2000 IR will be introducing a range of MOSFETs in the SO-8 package for this application.

IR's new secondary-side HEXFET^® power MOSFETs are optimized to work in isolated converters or for cross coupled and IC driven synchronous rectification with outputs of less than 5V. They feature fast switching with low gate charge, low R_DS(on) and a range of V_GS ratings from 12V to 30V to match application requirements. Package options include SO-8, D-Pak, D²Pak, TO-247 and Super-D²Pak^TM styles, the latter being ideal for applications with higher current handling needs.

"In the fast-paced DC-DC marketplace, customers need outstanding efficiency to sell their products," said Carl Blake, technical marketing manager for components at IR. "IR provides the products that allow customers to achieve benchmark performance at a range of power levels across their entire product line."

IR's new range of MOSFETs for DC-DC converters provides many options for designers including:

• reducing the overall system cost of a converter by increasing primary-side efficiency of the MOSFET to use less expensive Schottky diodes for the output rectification and still maintain overall efficiency;
• reduced heat and heat density using new secondary-side MOSFETs, potentially eliminating the need for a system heat- sink to greatly reduce system cost;
• higher switching frequencies to reduce the size and cost of magnetics
• the ability for the customer to either increase efficiency or reduce size and maintain efficiency.

"This announcement continues our initiative to provide DC-DC converter designers with the best performing and deepest set of component resources to meet the challenges facing them in the marketplace," said Blake. "We plan to continue this application- specific development program to accommodate high efficiency converter operations at ever lower output voltages and ever higher power levels."

Data sheets for these components are available from the IR Web site (www.irf.com) and Fax-On-Demand system (310-252-7100 USA and +44 1883 783 420 Europe).

Samples of all the new primary- and secondary-side MOSFETs are available online at DC2DC.irf.com. Production of these devices will commence by June, 2000. Pricing starts at $0.64 for 10,000 pieces for primary devices and at $0.63 for 10,000 pieces for secondary devices.