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    dc current gain variations

    Does hFE vary while BJT is in operation within the specified hFE min/max ranges?

    https://www.mouser.com/datasheet/2/4...01-1144060.pdf

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    Re: dc current gain variations

    It does not vary. The min to max range is specified to take account of type variations. If a transistor exemplar shows e.g. B=100 under specific condictions (like Vce=5V, Ic=1A, t=25°C), it will keep this current gain.


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    Re: dc current gain variations

    A transistor in operation heats or cools which affects its hFE.
    A transistor in operation has a variable current which also affects its hFE.
    Design a transistor circuit with enough base current so that it works with the minimum or maximum hFE for the varying conditions. Negative feedback is usually used.


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    Re: dc current gain variations

    Be aware though, that the specified Hfe is in the linear region. Which in this instance, it means a Vce of at least 5 volts.

    As the transistor approaches saturation, the Hfe will start to drop.
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