TO-247 4 Kelvin-sense package cuts IGBT switching losses

November 04, 2014 // By Graham Prophet
Infineon has added to its IGBT range by introducing a new variant of the popular TO-247 package. The TO-247 4 Kelvin-Sense package addresses the need for increased power density and space saving in applications striving for high efficiency.

When used together with Infineon's TRENCHSTOP 5 IGBT and Rapid diode technologies, the TO-247 4 package provides efficiency levels previously not available. Applications with PFC and inverter stages switching at greater than 20 kHz, will profit from the new package.

The 4-pin configuration offers a Kelvin-Sense connection to significantly reduce the emitter inductance in the gate driving loop. This is achieved by providing an additional connection to the IGBT emitter that serves as the reference potential for the driver. The 4-pin version enables customers to increase switching frequency in order to improve power density and reduce system costs. Comparing the TO-247 4-pin variant using TRENCHSTOP 5 IGBT and Rapid diode technologies with standard TO-247 3, the new package provides 20% lower turn-off losses and 15% lower turn-on losses. Combined, the total switching losses are reduced by about 20% leading to added efficiency.

Implementing the TO-247 4 package for an EU ENERGY STAR certified UPS, for example, enables power density to be doubled and efficiency to also be improved significantly. According to the ENERGY STAR organization, an ENERGY STAR certified UPS can cut energy losses in the range of 30 to 55%. Here the new package makes the task of the designer easier to achieve the efficiency goals.

In the TO-247 4 package, options are to have the co-packaged freewheeling diode, Rapid 1, optimised for low forward voltage (VF), or Rapid 2, optimised with low reverse recovery charge (Q rr). A demoboard is available to make the comparison between TO-247 3 and TO-247 4 packages.