Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

First transistor beta

Required integer input.

Second transistor beta

Required integer input.

Compute the Darlington pair current gain as the product of the two transistor betas. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Darlington beta

The resulting darlington beta returned as an integer.

• BJT calculations using a fixed current gain or junction drop are operating-point approximations. Gain, Early effect, saturation voltage, leakage, temperature, frequency, bias network loading, and safe operating area vary by device and conditions.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

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