How to get Iceo of a bipolar transistor ?

[m.mokhtar]

iceo in bipolar transistors

Hi rvery body,
If the datasheet of a bipolar transistor doesn't contain the parameter Iceo how to get it without any measurement .
Is the there a relationship between Icbo and Iceo ( I may remember there is a relationship but I forgot it if any)

 

[laktronics]

Hi,
Iceo = βIcbo , it gets multiplied by β, that is why you use a base resistance to ground without keeping base open in some switching circuits.
Regards,
Laktronics

 

[m.mokhtar]

Dear laktronics,
Many thanks you helped me a lot m I hope you will have an answer to the following question :
always there is a graph for β against Ic , so what value of β shall I use i.e at what Ic value ?.
Is it β at minimum Ic value available at the curve of β against Ic.
Many thanks for your previous help.
Best regards,
M.Mokhtar

 

[laktronics]

Hi,
Yes, it is true that the transistor β gets reduced both at high and low values of IC. So in normal usage one is expected to use the transistor around the mid value of the IC specified. But in your case, the leakage current being of very low value, I SUPPOSE you will use the lowest value of β only.
Regards,
Laktronics

 

[m.mokhtar]

I wanted to add the following information: For silicon transistors at Ic=0, B=0