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I haven't worked with electronics in a long time, and now have the task of measuring the power consumption of a low-power device I'm writing firmware for...

When the device is drawing very little current, the DC power analyzer shows the current oscillating(?). So, my question is, is the average current of a reading with peaks of 100uA and -100uA, around 0A? or is it something else?

My confusion is because I didn't expect to have negative and positive values in my reading. Any help is much appreciated!

I'm using the Data Logger function of the Keysight N6705C DC power analyzer.

p.s: Attaching the reading from the analyzer. (Avg:8uA, Peaks: -256uA, 887uA). The spikes in the reading are not the issue since they are triggered by periodic tasks in the MCU. My concern is the min, max, average indicated in the reading. enter image description here

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    \$\begingroup\$ I think you want an RMS value. Can your scope calculate that? \$\endgroup\$ – Hearth Mar 19 at 2:13
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    \$\begingroup\$ Add a 1 Hertz low pass filter. 100Kohm and 1uF is about right. \$\endgroup\$ – analogsystemsrf Mar 19 at 2:29
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    \$\begingroup\$ Which "the DC power analyzer"? How do we suppose to explain your observations if you failed to describe your set-up? \$\endgroup\$ – Ale..chenski Mar 19 at 3:31
  • \$\begingroup\$ I'm using a Keysight 6705C. I'll check to see if it does RMS value calculation. Does it makes sense to get the RMS value for DC? That is actually what I wanted to ask. \$\endgroup\$ – coder_mario Mar 19 at 18:28
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The positive and negative peaks in my reading seem to be some kind of measurement noise.

By using a 200uA range for the lowest parts of my signal, and a 100mA range for the spikes, I was able to get a cleaner trace of the ~5uA portion of the reading I was interested in.

Markers around a ~1uA region, using a 200uA range on the scope

Markers around the 800uA spike, using a 100mA range on the scope

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