Differential probe to read voltage across flyback SMPS output diode?

[treez]

Hello,
We wish to scope the voltage across the output diode in our offline , isolated flyback SMPS. (to see how high the ringing voltage goes) Should we use a differential probe, or will it be accurate enough to simply connect the actual scope probe directly?

 

[jamesd168]

Hello,
We wish to scope the voltage across the output diode in our offline , isolated flyback SMPS. (to see how high the ringing voltage goes) Should we use a differential probe, or will it be accurate enough to simply connect the actual scope probe directly?

I think it should be OK use a regular probe, typically the issue one should worry about is noise picked up from open circuit, but in your case you are measuring the voltage across a diode, the pickup noise should not be an issue.