Methods and systems of operating a double-sided double-base bipolar junction transistor

A switch assembly comprising:

• an upper terminal, a lower terminal, and a control input;
• a double-sided double-base bipolar junction transistor (DSDB-BJT) defining an upper base, an upper collector-emitter, a lower base, and a lower collector-emitter;
• an upper-main FET defining a first lead coupled to the upper terminal, a second lead coupled to the upper collector-emitter, and a gate;
• a lower-main FET defining a first lead coupled to the lower collector-emitter, a second lead coupled to the lower terminal, and a gate;
• a driver coupled to the control input, the gate of the upper-main FET, the gate of the lower-main FET, and the upper and lower bases of the DSDB-BJT;
• responsive to assertion of the control input, and for a first applied voltage across the upper terminal and lower terminal, the driver configured to arrange the DSDB-BJT for conduction of main load current from an upper terminal of the switch assembly, into an upper collector-emitter of the DSDB-BJT, through the DSDB-BJT, out through a lower collector-emitter, and then through the lower terminal of the switch assembly;
• and
• responsive to de-assertion of the control input, and for the first applied voltage, the driver configured to cease conduction of the main load current by:
• coupling the lower base of the DSDB-BJT to the lower terminal;
• and
• driving a pinch-off voltage to the lower collector-emitter to reduce reverse recovery current through the lower base.