AD8067 Self-oscillation?

Question

Hello! 
 I've selected AD8067 as a high speed Op Amp. 
 Schematic is quite usual and shown below 
 
 Power is dual, +/- 3 V. 
 I have output pulse form like shown below 
 
 Blue plot is for input and yellow is for output. 
 It is the most clear output signal, that I can get by R3 adjustment. 
 What can be the reason of such distorsion? 
 Thank you for answer!

FormerMember · Accepted Answer

KotNitro, 
 All op amps have input capacitance. You have high values of resistors around a fast op amp. 
 This is not good. Make all the resistors ten times smaller. 
 Also, the only purpose of R1 is input bias current cancellation, but with JFET inputs, you don't 
 really need R1 other than to limit the current if you have power supply sequencing problems. 
 Make it 1k. 
 Also, you need a cap, say 5-10 pF across the pot. 
 Harry)

FormerMember · Answer

I would suspect layout then. Breadboard or pcboard? Size of bypass caps? 
 How close to the package?

EZAdministrator · Answer

This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum. Thank you, EZ Admin

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AD8067 Self-oscillation?