HIGH-VOLTAGE PULSE GENERATION USING CURRENT MODE 2ND BREAKDOWN IN A BIPOLAR JUNCTION TRANSISTOR

The characteristics of a bipolar junction transistor operating in the avalanche region and then triggered into current mode second breakdown are formulated. If the time the BJT is subjected to secondary breakdown is limited the BJT may be used as a nanosecond, high voltage switch without sustaining damage. Several methods of fast pulse generation, electrical and optical, using this mode of operation are discussed. A 2000 V pulse generator, into 50 OMEGA, with a risetime of approximately 1 ns, jitter < 100 ps, is then designed using these results.