/// <summary>
/// Calculates the Undershoot related values
/// </summary>
/// <param name="undershootMaxTimeFWHMMultiplier">(Optional) The multiplier of the FWHM time to determine how long after the peak current time to search for undershoot (Default: 2.5x)</param>
private void CalculateUndershoot(double undershootMaxTimeFWHMMultiplier = 2.5)
{
if (undershootMaxTimeFWHMMultiplier <= 0)
{
throw new ArgumentOutOfRangeException("The Undershoot Max Time multiplier cannot be less than or equal to 0");
}
// Determine how much time after the max data point of the waveform to keep for Undershoot
double timeForUndershootDetectionAfterMaxTime = this.FullWidthHalfMaxValue * undershootMaxTimeFWHMMultiplier;
// Add the undershoot allowed time to the max data point time
double endTimeForUndershootDetection = this.PeakCurrentDataPoint.X + timeForUndershootDetectionAfterMaxTime;
// Trim the waveform, removing everything before the max peak
Waveform absoluteWaveformAfterPeakCurrentTime = this.AbsoluteWaveform.TrimStart(this.PeakCurrentDataPoint.X);
// Trim the end of the waveform from the max time until 2.5x the FWHM time
Waveform absoluteUndershootApplicableWaveform = absoluteWaveformAfterPeakCurrentTime.TrimEnd(endTimeForUndershootDetection);
// Find the (absolute) undershoot data point of the absolute Current waveform after the max time
DataPoint absoluteUndershootDataPoint = absoluteUndershootApplicableWaveform.Minimum();
// Look up what the undershoot max percent can be (it is a negative value)
this.UndershootAllowedMaximumPercent = CDMJS002WaveformCharacteristics.UndershootMaxPercent(this.SignedVoltage, this.IsLargeTarget, this.OscilloscopeIsHighBandwidth);
// Calculate what the maximum undershoot value can be (it is a negative number since we are referring to undershoot)
this.UndershootAllowedMaximumValue = this.PeakCurrentValue * this.UndershootAllowedMaximumPercent;
// Convert the absolute undershoot value to the signed value
double absoluteUndershootValue = absoluteUndershootDataPoint.Y;
// If the absolute undershoot is greater than zero, set it to zero. Otherwise set it to the signed value
if (absoluteUndershootValue > 0)
{
this.UndershootValue = 0;
}
else
{
this.UndershootValue = absoluteUndershootValue.InvertValueIfNegativePolarity(this.WaveformIsPositivePolarity);
}
// Determine if the Undershoot is passing
if (this.WaveformIsPositivePolarity)
{
this.UndershootIsPassing = this.UndershootValue >= this.UndershootAllowedMaximumValue;
}
else
{
this.UndershootIsPassing = this.UndershootValue <= this.UndershootAllowedMaximumValue;
}
// Create the undershoot signed Data Point
this.UndershootDataPoint = absoluteUndershootDataPoint.InvertYValueIfNegativePolarity(this.WaveformIsPositivePolarity);
}
/// <summary>
/// Calculates the Ring as a % of Ips
/// </summary>
private void CalculateRing()
{
double positiveLeadingEdgeNoiseValue = 0;
double negativeLeadingEdgeNoiseValue = 0;
if (this.compensateForNoise)
{
// (R&D experiment) A flag indicating that the noise reduction should use the peak-to-peak found in the zero line
bool useZeroLineStrategy = true;
// (R&D experiment) A flag indicating that the noise reduction should use a bessel-filtered waveform to remove the noise
bool useBesselFilterStrategy = false;
if (useZeroLineStrategy)
{
Waveform zeroLineBeforeTriggerWaveform = this.AbsoluteWaveform.TrimEnd(this.compensateForNoiseCutoffTime);
positiveLeadingEdgeNoiseValue = zeroLineBeforeTriggerWaveform.Maximum().Y;
negativeLeadingEdgeNoiseValue = zeroLineBeforeTriggerWaveform.Minimum().Y;
}
else if (useBesselFilterStrategy)
{
Waveform rawWaveform = this.AbsoluteIpsPlusPeakCurrentDerivationOffsetWaveform;
Waveform besselWaveform = BesselDigitalFilter.FilterWaveform(rawWaveform);
for (int i = 0; i < rawWaveform.DataPoints.Count(); i++)
{
positiveLeadingEdgeNoiseValue = System.Math.Max(positiveLeadingEdgeNoiseValue, rawWaveform.DataPoints.ElementAt(i).Y - besselWaveform.DataPoints.ElementAt(i).Y);
negativeLeadingEdgeNoiseValue = System.Math.Min(negativeLeadingEdgeNoiseValue, rawWaveform.DataPoints.ElementAt(i).Y - besselWaveform.DataPoints.ElementAt(i).Y);
}
}
}
// Find Ring1 Data point (max positive ring)
this.Ring1PeakDataPoint = this.AbsoluteIpsPlusPeakCurrentDerivationOffsetWaveform.DataPointAtHBM0OhmJS001MaximumRing(this.AbsoluteIpsPolynomial, positiveLeadingEdgeNoiseValue, true);
// Find Y-value of FifthDegreePolynomial at the time of Ring1
double positiveRingLeastSquaresFitValue = this.AbsoluteIpsPolynomial.Evaluate(this.Ring1PeakDataPoint.X);
// Find the difference between Ring1 and Ring1FDP
double positiveRingCurrentDifference = this.Ring1PeakDataPoint.Y - positiveRingLeastSquaresFitValue;
// Find the absolute value of the difference between Ring1 and Ring1FDP
double positiveRingCurrentDifferenceAbs = System.Math.Abs(positiveRingCurrentDifference);
// Find Ring2 Data point (max negative ring)
this.Ring2PeakDataPoint = this.AbsoluteIpsPlusPeakCurrentDerivationOffsetWaveform.DataPointAtHBM0OhmJS001MaximumRing(this.AbsoluteIpsPolynomial, negativeLeadingEdgeNoiseValue, false);
// Output the Ring2 DataPoint (max negative ring)
// Find Y-value of FifthDegreePolynomial at the time of Ring2
double negativeRingLeastSquaresFitValue = this.AbsoluteIpsPolynomial.Evaluate(this.Ring2PeakDataPoint.X);
// Find the difference between Ring2 and Ring2FDP
double negativeRingCurrentDifference = this.Ring2PeakDataPoint.Y - negativeRingLeastSquaresFitValue;
// Find the absolute value of the difference between Ring2 and Ring2FDP
double negativeRingCurrentDifferenceAbs = System.Math.Abs(negativeRingCurrentDifference);
// Add the two differences to get Ir
double totalRingCurrent = positiveRingCurrentDifferenceAbs + negativeRingCurrentDifferenceAbs;
// Determine the ringing % compared to Ips
this.TotalRingPercentValue = totalRingCurrent / System.Math.Abs(this.PeakCurrentValue);
// Determine whether the ringing % is passing
this.TotalRingIsPassing = this.TotalRingPercentValue <= this.TotalRingAllowedMaximum;
}