You are right in noticing that hFE is a function of Ic, and also to some extent Vce. You could find the _typical_ value of hFE at different Ic and Vce from the hFE graph, usually supplied by the manufacturer in the datasheet. However, not the absolute value, as this is device specific.Originally posted by Steve1992@Apr 30 2006, 12:21 PM
On data sheets hFE will be quoted at Ic
eg hFE or β = 110-900 at 1mA(Ic).
If im working on a common-emitter bipolar amp:
Ib = Vcc - Vbe / Rb
So I know the base current.
Ic = Vcc - Vbe / ( Rb / β )
What β should I use?
110-900
steve
[post=16704]Quoted post[/post]