The low temperature switching performance of thyristors and MOSFETs

The measured switching performance of MOS-controlled thyristors (MCTs), an SCR (silicon-controlled rectifier), and a power MOSFET are discussed for operating temperatures from 25 to -180 degrees C. Current pulses of up to 340 A were conducted for a duration of 10 mu s. A comparison of the energy losses, switching times, and device behavior as a function of temperature is also presented. It is shown that under controlled situations, the MCT compares favorably when used at low ambient and junction temperatures. These devices turn on quickly enough to keep the switching losses small when conducting large currents, though at low current levels and high frequencies the MOSFET is still the superior device because of its very fast turn-on. Based on conduction losses at high current levels, the MCTs outperformed the other test devices.<>