PPK2 showing noise in Source Mode graph

[shstapleford]

During a power profile in source mode I am getting about 300uA of noise. When the unit is moved the noise seems to away. I have checked the grounds and everything is secure. I have a process that runs every 1s you can see on the graph but the current floor should run at about 40uA. I have checked this on some other meters and everything is correct but on the PPK2 I am getting some noise generated that seems to go away whenever it it touched or moved (seen on the very right of the readout).

 

[Marjeris Romero]

Hi,

I am sorry for the late reply.

Could you try to zoom where the noise is? And see if there is the spikes have a frequency? Even better if you are able to upload the PPK files here, there is an option to export the measurements into a PPK format in the left menu bar:

But it's not normal that the PPK2 gives so much noise. If the frequency of the spikes are 30-50ms interval it could be "refresh spikes" from the regulator in the chip, which will have some current burst when it's in idle, refresh mode, which is normal. If the noise interval is closer to 1ms it could be noise from the USB peripheral.

Best regards,

Marjeris

[shstapleford]

I added a 1N34A in line with the power and that seemed to fix it. Maybe some ground loop effect between the DUT and the PPK2. Made about a 1 to 2uA reading difference but for our purposes that solved the issue.