poynt99's Testing of Rosemary Ainslie's Circuit 2013-06

[poynt99]

First test will be conducted to establish the polarity of Pbat for the condition where the battery energy is depleting. Once known, we will have a baseline to compare against our measurements on the actual circuit.

[poynt99]

DSO Limitations

While taking some measurements I noticed that the "mean" of any trace will have a slight variance in value depending on where it is placed vertically on the scope screen. The degree of variance is enough to be of a concern, so I made a video illustrating this particular limitation one should be aware of when using DSO's. I've also outlined a method to virtually eliminate this slight flaw and get the most out of your critical measurements. Tektronix gives you the ability to add an offset to any trace, and doing so seems to eliminate this measurement artifact. I am not certain if Lecroy or Agilent, or any other DSO brands have this feature.

I will be utilizing this method whenever I can in the upcoming measurements.

The video will follow shortly.

[poynt99]

Here's that video demonstrating the variance of the mean measurement value on a trace as it transitions from bottom to top of the screen. Assigning a counter-DC offset to the trace seems to correct this scope artifact.

http://www.youtube.com/watch?v=4p4EwIW5YWU

[poynt99]

This video demonstrates the use of a simple DC circuit to establish the polarity of the battery power measurement as per the connections on the schematic. In this case the polarity is POSITIVE. This circuit of course exhibits a battery whose energy is DEPLETING.

As such for the tests which will follow, a battery power measurement that is positive will indicate that energy is being depleted in the battery, and a measurement that is negative will indicate that the energy is being increased in the battery.

http://www.youtube.com/watch?v=iTZA4iY38Ds

[poynt99]

Attached is a drawing of the circuit I'll be testing with added protection and CSR components.