New Industry Products

Toshiba Adds Low On-State Resistance MOSFETs For Secondary Stage Of Switched Mode Power Supplies

March 26, 2009 by Jeff Shepard

Toshiba America Electronic Components, Inc. (TAEC) introduced a new series of MOSFETs for synchronous rectification in the secondary stage of switched mode power supplies (SMPS). Four new devices, developed by Toshiba Corp. (Toshiba), are optimized with low on-state resistance (RDS(ON)) to reduce power loss in the secondary stage of SMPS.

The first four MOSFETs in this product lineup are targeted for use in ac power adapters or AC-DC power supplies in computing, and consumer electronics applications. Three 75V devices and one 100V device can each be used as either the switch or synchronous MOSFET in the secondary stage of a SMPS.

"In loss simulation testing, Toshiba found that the RDS(ON) in a secondary stage MOSFET is the most critical factor related to power loss, typically accounting for 50 to 70 percent of the loss," said Jeff Lo, Business Development Manager, Discrete Power Devices, for TAEC. "As a result, Toshiba developed these low RDS(ON) devices to improve power efficiency."

Three 75V devices provide a choice of current rating, RDS(ON) and packaging. The TK40A08K3 has a current rating of 40A with RDS(ON) (typ.) of 7.0 mΩ, and is offered in a TO-220SIS package (TO-220F isolated). The TK80A08K3 has a current rating of 80A, RDS(ON) (typ.) of 3.6 mΩ and is offered in a TO-220SIS package. The 75V, 80A TK80D08K3 has similar electrical characteristics to the TK80A08K3, but is offered in a non-isolated TO-220(W) package (TO-220AB).

The fourth new MOSFET, TK40A10K3, is a 100V, 40A device with RDS(ON) (typ.) of 11.5 mΩ, and is offered in a TO-220SIS package.

Samples and mass production of the new Toshiba UMOS IV MOSFETs for synchronous rectification in SMPS are available now. Prices in sample quantities start at $0.80.