very basic bjt model 01 PUBLIC

Very basic transistor model with diode for Vbe and CCCS for current gain.

Very basic transistor model with diode for Vbe and CCCS for current gain.

Dbc models collector base diode, which slightly forward biases under heavy collector saturation.

Note diode clamp at collector to represent collector-emitter saturation (Vcesat). This simple model of collector saturation is not well suited to generic transistor model usage in anything other than this test circuit because the Vx source could generate currents that a real bjt would not.

Right click on Q1 > Edit parameters and note that B_F = 140

This is the nominal beta.

At 1mA base current from I1 note that there is a knee in the
Ic curve at approximately 140mA.

To the left of this knee the "transistor" is in saturation.

To the right of this knee, the transistor is in (forward) active region.

Simulate > DC Sweep > Run DC Sweep

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