> Hello all, I am trying to find three characteristics of the LF351 op-amp.
>
> Ao = Low Frequency Gain (in dB or V/V)
> Fb (some call it Fp) = Corner Frequency (frequency where gain is -3 dB)
> Ft = frequency at which the gain is 1 (0 dB)
>
> I know that Ao * Fb = Ft
>
> and from the datasheet on www.national.com I _BELIEVE_ that Ao =
> 100,000 V/V (100 dB) and Ft = 4 Mhz (4 *10^6 Hz)  but when I plug
> all the numbers in... I get a corner frequency of 40 Hz!  There
> is no way that is a correct corner frequency.  Any help would be
> greatly appreciated.

     That sounds about right, remember since you are using a finite Ao the
amplification of 100dB only lasts for a few Hz. The corner freq will change
depending on what gain you plan to use the Op Amp at, you are currently
figuring out the corner freq at open loop gain. Hope this helped, TTYL

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
"[PIC]:" PIC only "[EE]:" engineering "[OT]:" off topic "[AD]:" ad's