guest Post subject: Breakdown voltages affects in BJT/HBT Posted:
Wed Feb 08, 2006 8:20 pm Hello people: I am a student and
I need to clarify a point. This questino relates to integrated cirucit
transistor and not discrete transistors. I am using HBT (basically
BJT structure) and I was doing DC sweep. When I had just one HBT device
and I ran the sweep from IBB=10u to 80uA with VCE=0 to 2.5 it works
fine. But when I have two same devices in parallel and I did
DC sweep for the same ranges I get the warning that the base-emitter
and base-collector are in reverse bias breakdown. This seems
counter intiutative (may be just because of my lack of knowledge). I
thought that now that I have two devices in parallel, the overall transistor
should be able to handle more current or at least the same amount of
current as the single device and should have the same voltage limiations
as the single device because the two devices are in parallel. Why do
you think the device is breakdown? Doesn't parallel mean that the collector
and base of the two devices are connected together? Thank you.
Marc Posted 11/12/2012
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