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In Reply to: Ocampo oscillating how to stabilize posted by jk on December 29, 2016 at 08:16:10:
Not knowing what is causing the oscillation - design flaw, poor layout (stray capacitance), wrong opamp choice for the application, etc.
Just for grins, I would try a 0.1uF cap at -V to ground and +V to ground, as close as possible to the opamp +V and -V pins keeping all leads as short as possible.
Also, stray input capacitance can cause stability issues. Signal phase shifts can occur which may result in oscillation. The effects of stray input capacitance can be minimized with a small capacitance placed in parallel with the feedback resistor. Try 10pF. High frequency gain and noise will be reduced with a feedback capacitor.
Stray output capacitance can also cause stability problems. Placing a low value resistor (~100 ohm) in series with the opamp output will isolate it from the stray output capacitance.
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Follow Ups
- RE: Ocampo oscillating how to stabilize - AbeCollins 15:23:44 01/03/17 (2)
- RE: Opamp oscillating how to stabilize - jk 11:29:54 01/16/17 (0)
- RE: Ocampo oscillating how to stabilize - jk 19:34:32 01/03/17 (0)