Development of Gate and Base Drive Using SiC Junction Field Effect Transistors

A base drive and a gate drive were designed with 4H-SiC junction field effect transistors JFET and worked. Developmental JFET had uneven distribution of performance parameters. For example, the gate current Ig and voltage Vgs of each JFET required precise, customized control. This initial investigation designed and tested two JFETs into a base drive circuit board for an npn SiC bipolar junction transistor BJT. The circuit rapidly drove a SiC BJT on and off with 4H-SiC semiconductor devices to perform to 150 C. For the gate of an n-MOS or insulated gate bipolar transistor IGBT two other JFETs were designed into a drive circuit which worked. For these JFETs Id - Vds curves and reliability degraded moderately with use.