International Rectifier Corp. has introduced a series of IGBTs whose improved turn-off characteristics make them a cost-effective alternative to power MOSFETs in high-frequency switching circuits, according to the company.
The 600V IGBTs, designated the WARP2, exhibit lower conduction losses than power MOSFETs of comparable voltage, enabling them to provide higher current density while operating at frequencies up to 150kHz, said Bhasy Nair, marketing manager of the AC/DC sector at IR, El Segundo, Calif.
IGBTs have long been used in lower-frequency applications such as motor controls, but their slow turn-off characteristics and tendency to exhibit tail current has precluded them from being used in switching power supply circuits in which frequencies often exceed 100kHz, Nair said.
By employing thin-wafer technology, IR's IGBTs turn off faster with negligible tail current, he said. This reduces switching losses and keeps conduction losses constant, allowing the devices to operate efficiently in a current-share mode when wired in parallel. MOSFETs, by contrast, exhibit higher conduction losses as their current increases, according to Nair.
IR in recent years has tried to differentiate itself by making more specialized products that can carry higher prices. But the WARP2 IGBTs are priced competitively with MOSFETs, said Nair, who expects the devices to be designed into telecommunications, server, and consumer power supplies.
The WARP2 series comes in 20, 35, or 50A versions in a TO-247 package, as well as a 20A version in a TO-220. The 50A device provides 85% more current than a 600V MOSFET in a TO-247, and the 20A part handles 18% more current than a 600V MOSFET in a TO-220, according to the company.
The IBGTs are packaged with IR's Hexafred co-pack diode, which the company said provides higher speed and faster recovery than the parasitic body diodes in MOSFETs.
In quantities of 10,000, the WARP2 is priced at $1.03 for the 20A IRG20B60PD1 in a TO-220.