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AD797 as non-inverting buffer

Question asked by three21mark on Jul 6, 2012
Latest reply on Jul 6, 2012 by charlyelkhoury

Can the AD797 be used as a non-inverting buffer?  I followed the circuit guidance in the data-sheet (figure 37), but the circuit is oscillating at about 900 KHz.  Table 6 on the data sheet lists the recommended circuit values for the follower circuit, but does not include a gain of one. I know its sometimes hard to "tame" this part.  I have used it in the past but always at higher gains.  My application is that I need a low noise non-inverting buffer (A=1) with a flat bandwith out to beyond 100 KHz. My source impedance is low, so the AD797 is a good choice.  I also noticed that there are no closed-loop gain plots in the data-sheet?

 

Now I'm looking at the ADA4004.  The data sheet does show the closed-loop gain (figure 19) and shows a gain = +1 plot.  Would the the ADA4004 be a better choice?  Maybe its less finicky to circuit layout etc?

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