Products > Test Equipment

Measuring power supply ripple with Siglent 1202X-E

<< < (7/16) > >>

nctnico:
But how much of that noise comes into your scope through the ground and how much is actually between the +/- of the PSU?

And measuring with a capacitor in parallel is not a bad idea because that is how most power supplies are used in the end.

BillyO:

--- Quote from: nctnico on September 02, 2023, 05:22:43 pm ---But how much of that noise comes into your scope through the ground and how much is actually between the +/- of the PSU?

--- End quote ---
I have shown ambient traces (everything connected but PS off).  I have also ensured that the ground from the probe to the PS is less than (much less than) 1cm.  The noise being shown is being created by the PS.

nctnico:

--- Quote from: BillyO on September 02, 2023, 05:28:29 pm ---
--- Quote from: nctnico on September 02, 2023, 05:22:43 pm ---But how much of that noise comes into your scope through the ground and how much is actually between the +/- of the PSU?

--- End quote ---
I have shown ambient traces (everything connected but PS off).  I have also ensured that the ground from the probe to the PS is less than (much less than) 1cm.  The noise being shown is being created by the PS.

--- End quote ---
Yes, but is the noise between +/- or ground induced? It is quite possible the PSU is pushing HF current through the ground connection of the probe which then shows up at the input. A differential measurement is much better.

BillyO:

--- Quote from: nctnico on September 02, 2023, 06:03:47 pm ---Yes, but is the noise between +/- or ground induced? It is quite possible the PSU is pushing HF current through the ground connection of the probe which then shows up at the input. A differential measurement is much better.

--- End quote ---
I don't have a differential probe and one that could catch those spikes would likely cost more than a new car so won't be happening anytime soon..

What I can do is ground the negative on the DC side and see if that makes a difference.

nctnico:

--- Quote from: BillyO on September 02, 2023, 06:08:15 pm ---
--- Quote from: nctnico on September 02, 2023, 06:03:47 pm ---Yes, but is the noise between +/- or ground induced? It is quite possible the PSU is pushing HF current through the ground connection of the probe which then shows up at the input. A differential measurement is much better.

--- End quote ---
I don't have a differential probe and one that could catch those spikes would likely cost more than a new car so won't be happening anytime soon..

What I can do is ground the negative on the DC side and see if that makes a difference.

--- End quote ---
What you can try is reverse +/- and see which part of the noise flips up-side-down and what remains the same.

Navigation

[0] Message Index

[#] Next page

[*] Previous page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod