power profiler showing negative current.

[Stratosphere]

Power Profiler V2.3.1

Hi,

I recently started doing power testing on one of our boards using the power profiler kit. I wanted to tested current consumption at different operating voltage levels. When setting the voltage regulator to 3.0V, the current curve seemed fine and as I started lower the voltage, the overall current (and idle current) started to go down as expected. But at 2.3V or below I started seeing negative current values. There is no battery or other power source attached to our custom board and it is powered solely through the pkk so it couldnt be another source back feeding. 

Reading through some of the other posts, there were mentions of changing some setting in some file but I can't seem to find anything in the power profler that i can customize. 

Please suggest possible fix to the issue. It is a brand new power profiler kit and it had never been used before.

Thanks your all the help in advance.

Noaman 

[Stian Røed Hafskjold]

Hi, is the PPK stacked on top of the DK? If so you need to have the regulator select switch in the DK position. If you want to use the PPK on board regulator the PPK and DK must be connected with a SWD cable.

[Stratosphere]

Hi Stian,

Thanks for your response. I tried the setup as you suggested and it is working. I did have to update the firmware on the ppk though as it just wouldn't respond to any commands nor show any current curves.

Thanks you