Methods of operating a double-base-contact bidirectional bipolar junction transistor
Methods, systems, circuits, and devices for power-packet-switching power converters using bidirectional bipolar transistors (B-TRANs) for switching. Four-terminal three-layer B-TRANs provide substantially identical operation in either direction with forward voltages of less than a diode drop. B-TRANs are fully symmetric merged double-base bidirectional bipolar opposite-faced devices which operate under conditions of high non-equilibrium carrier concentration, and which can have surprising synergies when used as bidirectional switches for power-packet-switching power converters. B-TRANs are driven into a state of high carrier concentration, making the on-state voltage drop very low.
1. A method for switching a power semiconductor device which includes both an n-type emitter/collector region, and also a p-type base contact region, on each of both first and second opposing surfaces of a p-type semiconductor die, comprising:
in the ON state, when an external voltage difference is applied between the emitter/collector regions, flowing base current through the base contact region which is nearer the more positive one of the emitter/collector regions, without flowing base current through the other of the base contact regions;
wherein the base contact region on the first surface is not electrically connected to the base contact region on the second surface, except through the semiconductor die itself, if not counting the applied external voltage difference;
and wherein the emitter collector region on the first surface is not electrically connected to the emitter collector region on the second surface, except through the semiconductor die itself;
whereby bidirectional switching is achieved with an on-state voltage drop which is less than a diode drop between the semiconductor die and a respective one of the emitter/collector regions.