How to convert hFE to Beta for bipolar transistors?

[Khabree]

hfe bjt

What I know is that in H-parameter the current gain (beta) is Hfe.

 

[laktronics]

hfe definition transistor

Hi,
A nice thread with a lot of discussions and hot debate, still it appears no consensus have evolved. I also used to follow what FVM and AudioGuru have been telling, i.e., hFE is DC current gain for the active region and hfe is small signal A.C. current gain for any frequency. The idea of using the 'small signal' term is to ensure that AC signal does not affect the DC biasing. And in this part of the world, these transistors seem to be obeying these definitions with out any problem.

Regards,

 

[zlatkoMM]

hfe vs beta

WOW that is electronic

 

[Kral]

hfe bipolar

zlatkoMM,
hFE is the collector current divided by the base current in the common emitter configuration (DC current gain).
.
hfe is the slope of the collector current with respect to base current in the common emiiter configuration (AC current gain)
Regards,
Kral.

 

[Audioguru]

bipolar transistor hfe

Hi Krai,
The datasheets say the same as you but school kids don't believe it. Maybe the school kids don't understand. Maybe their teachers don't understand.

 

[xtra500000]

Re: hfe vs ß-dc

ß-ac=hfe

ß-dc=(1+ß-ac)

=> ß-dc=(1+hfe)

=>ß-dc ≈ hfe

As ß is higher,so addition of 1 shows less difference.
But in Darlington connection it show the difference.

let hfe=25 => ß-dc =26

so the over all current gain is 676 ,if only hfe then its 625. so the difference