Power

The power harness is used to measure and validate the current consumption. It integrates with ‘pytest’ to perform automated data collection and analysis using a hardware power monitor.

The harness executes the following steps:

  1. Initializes a power monitoring device (e.g., stm_powershield) via the PowerMonitor abstract interface.

  2. Starts current measurement for a defined measurement_duration.

  3. Collects raw current waveform data.

  4. Uses a peak detection algorithm to segment data into defined execution phases based on power transitions.

  5. Computes RMS current values for each phase using a utility function.

  6. Compares the computed values with user-defined expected RMS values.

harness: power
harness_config:
  fixture: pm_probe
  power_measurements:
    elements_to_trim: 100
    min_peak_distance: 40
    min_peak_height: 0.008
    peak_padding: 40
    measurement_duration: 6
    num_of_transitions: 4
    expected_rms_values: [56.0, 4.0, 1.2, 0.26, 140]
    tolerance_percentage: 20

  • elements_to_trim – Number of samples to discard at the start of measurement to eliminate noise.

  • min_peak_distance – Minimum distance between detected current peaks (helps detect distinct transitions).

  • min_peak_height – Minimum current threshold to qualify as a peak (in amps).

  • peak_padding – Number of samples to extend around each detected peak.

  • measurement_duration – Total time (in seconds) to record current data.

  • num_of_transitions – Expected number of power state transitions in the DUT during test execution.

  • expected_rms_values – Target RMS values for each identified execution phase (in milliamps).

  • tolerance_percentage – Allowed deviation percentage from the expected RMS values.