Transistor Biasing Calculator

Calculate BJT biasing resistors for common emitter configuration. Operating point. Gain estimation.

Transistor Type

Biasing Method

Vcc (V)

Desired Ic (mA)

Beta (hFE / Current Gain)

Vbe (V) - typically 0.7

Rc (Collector Resistor, Ohms)

2N2222 (NPN): Beta 100-300, Ic max 800mA, Vce max 40V

2N3904 (NPN): Beta 100-300, Ic max 200mA, Vce max 40V

BC547 (NPN): Beta 110-800, Ic max 100mA, Vce max 45V

2N3906 (PNP): Beta 100-300, Ic max 200mA, Vce max 40V

BC557 (PNP): Beta 125-800, Ic max 100mA, Vce max 45V

TIP31 (NPN): Beta 25-50, Ic max 3A, Vce max 40V

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