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Design >> Analog Design >> Transition Frequency
https://designers-guide.org/forum/YaBB.pl?num=1077010435

Message started by Abe on Feb 17^th, 2004, 1:33am

Title: Transition Frequency
Post by Abe on Feb 17^th, 2004, 1:33am

Hi,
What's the difference between Transition Frequency(ft)
and unity gain frequency?

thanks,

Title: Re: Transition Frequency
Post by jeffyan on Feb 17^th, 2004, 6:35am

I guess whether Transition Frequency(ft) is equal to
f(-3db) !

Title: Re: Transition Frequency
Post by Abe on Feb 17^th, 2004, 10:09pm

f(-3db) is the dominant pole frequency, it's not the
ft or unity gain frequency, anybody else has any
feedback

thanks,

Title: Re: Transition Frequency
Post by Humungus on Feb 18^th, 2004, 1:01am

transition frequency and unity gain frequency are exactly the same.

Title: Re: Transition Frequency
Post by Mighty Mouse on Feb 18^th, 2004, 8:50am

f_T is defined as the frequency at which the current gain of the device drops to unity.

- MM -

Title: Re: Transition Frequency
Post by yeow on Feb 21^st, 2004, 2:32pm

We generally use unity gain bandwidth for one stage ot
two stages op-amp. Therefore unity gain frequency
is a general term.

ft is more for bipolar transistor, it is measured or calculated using a common-emitter circuit