Test Execution 1

Finished creating test plan and the associated test matrixes:
- Test plan (word document) can still use some fine tuning in the procedure
- Test matrixes (excel document) will also require some fine turning, but the skeleton is good
Important notes:
- Measured the actual resistor values for the input voltage sensor, they are allowing for a much more accurate reading
- The voltage at the output of the input power multiplexer differs from the output of the PSU, the difference is not negligible because of:
  - The voltage drops bit over the power supply lead wires, they are pretty thick so it isn't that much, maybe a few 10s of mV
  - Between the power supply lead wires and the input terminal block are ~20 awg wires, this caused the unloaded DUT to drop by over 100 mV
  - The transistors in the the power supply multiplexer also have an R-on value, causing the voltage to drop another 20mV or so
  - ***The DUT was unloaded, drawing a max of 150mA from the power supply, so for load and line regulation the voltage drop would be significant
  - Therefore, for measuring DC input voltage, will take the voltage at the output of the power multiplexer
- Will make an LCD 'smoke test' at a later date, I know it works, but it would be good to make a test program that verifies control and that every pixel can be written to
- Current sensor calibration might as well be part of ADC testing as I cannot directly measure the current sense resistor, and getting a constant current of any value, especially 500mA will be time consuming, might as well only do it once
- The resistors for the output current sensor are not electrically isolated from the feedback circuitry for the buck-boost converter, so I cannot get an accurate measurement of them with the DMM
- For the priority multiplexer, Case A : TST-02-A3 fails. The voltage values at the nodes between the input power multiplexer and the output of the priority multiplexer are iteresting... I will record the value of each node at every step in the case to determine what the issue is
- Oscilloscope:
  - Will be acquiring the ripple voltage waveforms of the input output voltage in "HR" mode, voltage waveforms are more consistent in this mode than "Normal" and "Average Mode"
    - Also, this seems to be the common practice:
      - Measuring ripple voltage
      - Google Gemini
  - Tried using the ground spring instead of the 'long-lead probe' for higher accurate waveform measurement, doesn't seem to make a difference, will verify later

Prep for Testing 9

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