To confirm if HFE of a bc549 I found is good

fiatuno · Feb 24, 2012

I wish to confirm the hfe β of the bc549 which I found to be 110 from the below website:
http://eu.mouser.com/Search/Refine.aspx?Keyword=bc549
but from the datasheet the values are vague. Can anyone please help. Thanks in advance.
Regards,
FiatUno

crutschow · Feb 24, 2012

The hFE values are not vague, there is just a manufacturing variation from a minimum of 110 to a maximum of 800 and the value you get depends upon the particular transistor you happen to buy. This variation is typical of any transistor although some have a smaller variation.

So the circuit you use it in needs to be designed to operate properly with an hFE variation over that range. You never design a circuit that requires a particular value of beta to operate correctly.

To confirm if HFE of a bc549 I found is good

fiatuno Thread Starter Member

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