Gummel plot

SiGe HBT Gummel plot

In electronics, the Gummel plot is the combined plot of the base and collector electric currents, $I_{{\text{c}}}$ and $I_{{\text{b}}}$ , of a bipolar transistor vs. the base–emitter voltage, $V_{\text{be}}$ , on a semi-logarithmic scale. This plot is very useful in device characterization because it reflects on the quality of the emitter–base junction while the base–collector bias, $V_{\text{bc}}$ , is kept constant.

A number of other device parameters can be garnered either quantitatively or qualitatively directly from the Gummel plot:^[1]

the common-emitter current gain, $\beta$ , and the common-base current gain, $\alpha$ ,
base and collector ideality factors, $n$ ,
series resistances and leakage currents.

Sometimes the DC current gain, $\beta$ , is plotted on the same figure as well.

References

^ A. S. Zoolfakar et N. A. Shahrol, «Modelling of NPN Bipolar Junction Transistor Characteristics Using Gummel Plot Technique», in 2010 International Conference on Intelligent Systems, Modelling and Simulation (ISMS), 2010, p. 396–400.

[1] A. S. Zoolfakar et N. A. Shahrol, «Modelling of NPN Bipolar Junction Transistor Characteristics Using Gummel Plot Technique», in 2010 International Conference on Intelligent Systems, Modelling and Simulation (ISMS), 2010, p. 396–400.

[1]

Gummel plot

See also

References