The Gummel-Poon model is a compact model for bipolar junction transistors (BJT) which also takes into account effects of low currents and at high-level injection. Fig. C.1 shows the equivalent circuit of the Gummel-Poon model.
The model distinguishes four operating regions. The base and collector current as they are implemented in SPICE [45] are as follows.
Ic = | ![]() |
(C1) |
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(C2) |
Ic = | ![]() |
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(C3) | |
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(C4) |
Ic = | ![]() |
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(C5) | |
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(C6) |
Ic = | ![]() |
(C7) |
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(C8) |
In these equations Gmin is the minimum conductance which is automatically switched in parallel to each pn-junction.