Title :
The switching operation of power BJTs at low voltages
Author :
Irvine, D.R. ; Gosbell, V.J. ; Platt, D.
Author_Institution :
Dept. of Electr. & Comput. Eng., Wollongong Univ., NSW, Australia
fDate :
29 Jun-3 Jul 1992
Abstract :
The switching behavior of power BJTs at low voltages is investigated and compared with high-voltage operation to gain understanding of transistor behavior in soft-switching circuits. A one-dimensional model of the power transistor based on semiconductor physics is used to simulate the switching operation of a power BJT in a chopper circuit under both high and low voltage supply conditions. Simulation results are verified by experiment, and a physical description of the switching process at low voltages is presented. The transistor is found to operate in quasi-saturation during both the rise and fall times when operating with a low voltage supply, resulting in much longer rise and fall times. The phenomenon of current tail is also investigated and is found to be a problem at low voltages as well as high voltages
Keywords :
bipolar transistors; choppers (circuits); power transistors; switching circuits; bipolar junction transistor; chopper circuit; high-voltage operation; low voltages; power BJT; quasi-saturation; soft-switching circuits; switching operation; Choppers; Circuit simulation; Diodes; Low voltage; Physics; Power semiconductor switches; Power transistors; Predictive models; Switching circuits; Zero voltage switching;
Conference_Titel :
Power Electronics Specialists Conference, 1992. PESC '92 Record., 23rd Annual IEEE
Conference_Location :
Toledo
Print_ISBN :
0-7803-0695-3
DOI :
10.1109/PESC.1992.254790