Guys hi,
Hope for some advice as I am not sure where to look.
I have a a simple microcontroller-based pulse generator which shoots nice square pulses when no load is connected.
The micro outputs a signal which is then fed to a AD8030-based voltage buffer which according to the specs is capable of sourcing/sinking ~ 160ma of current.
Now when there is no load, there is no problem - i see beautiful square waves. When i connect a resistive load, i start seeing the waveform oscillating 15-20% around its nominal peak value (please see attached image).
At first i thought, maybe the load draws so much current that the opamp cannot provide it, but when measured, the current is much less than the specified in the sheet (~20 ma). I put a 47u capacitor next to the opamp power supply but this shouldn't help since i see the voltage oscillating, not dropping. Indeed - it had no effect : i still observe this annoying oscillation.
Would appreciate an advice from an expert.
Kind regards,
Lenny
Hope for some advice as I am not sure where to look.
I have a a simple microcontroller-based pulse generator which shoots nice square pulses when no load is connected.
The micro outputs a signal which is then fed to a AD8030-based voltage buffer which according to the specs is capable of sourcing/sinking ~ 160ma of current.
Now when there is no load, there is no problem - i see beautiful square waves. When i connect a resistive load, i start seeing the waveform oscillating 15-20% around its nominal peak value (please see attached image).
At first i thought, maybe the load draws so much current that the opamp cannot provide it, but when measured, the current is much less than the specified in the sheet (~20 ma). I put a 47u capacitor next to the opamp power supply but this shouldn't help since i see the voltage oscillating, not dropping. Indeed - it had no effect : i still observe this annoying oscillation.
Would appreciate an advice from an expert.
Kind regards,
Lenny
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