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

A switch assembly comprising:

• an upper terminal, and a lower terminal;
• a transistor defining an upper base, an upper collector-emitter, a lower base, and a lower collector-emitter;
• an upper current source having a sink input coupled to the upper terminal and a source output;
• 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;
• and
• a controller coupled to the gate of the upper-main FET and the gate of the lower-main FET, and for a first applied voltage across the upper terminal and lower terminal, the controller configured to:
• assert the gate of the upper-main FET;
• assert the gate of the lower-main FET;
• configure the upper current source to provide a first turn-on current to the upper base of the transistor by driving the first turn-on current from an upper power converter based on a first upper feedback derived from an output voltage of the upper power converter, and then to provide a first steady-state current to the upper base by providing the first steady-state current from the upper power converter based on a second upper feedback derived from current provided by the upper power converter, the first steady-state current lower than the first turn-on current.