Teledyne SP Devices ADQ14, User Manual

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Classification Revision
Public PA1
Document ID Print date
18-2074 2018-04-06
4.8.1 Pulse Width
The pulse width is computed as the number of samples between the pulse trigger and reset level. This
value will wrap if the pulse width is larger than 2
16
- 1 samples.

Note
The pulse width metadata value will wrap if the pulse length is larger than 2
16
- 1 samples.
4.8.2 Pulse Peak Value
The maximum value or the minimum value of the pulse. For positive pulses the peak is defined as the
maximum value, and for negative pulses the peak is defined as the minimum value
The peak is a 16-bit signed value.
4.8.3 Pulse Peak Value Timestamp
The peak value timestamp is the sample index at which the extreme value occurred, relative to the record
header timestamp. That is, the time in samples between the detection window trigger and the extreme
value.
The timestamp is a 32-bit unsigned value and will wrap if the distance between the detection window
trigger and the pulse is larger than 2
32
- 1 samples.
If the peak value is reached at multiple samples, the timestamp value will report the last one.

Note
The timestamp value will wrap after 2
32
- 1 samples.
4.8.4 Overflow
The pulse characterization module can on average process 500 million pulses / second at 2 GSPS and
250 million pulses / second at 1 GSPS. The module will buffer up to 2048 pulses at 2 GSPS (1024 pulses
at 1 GSPS) after which the characterization module overflows.
An overflow condition will set a sticky status bit which can be read with the API call
PDGetCharacterizationStatus()
.
The status bit is cleared when calling
PDSetupCharacterization()
.

Note
The pulse characterization module can, on average, process 500 million pulses / second at 2 GSPS
and 250 million pulses / second at 1 GSPS.
4.9 Histograms
The firmware histogram module provides histograms for the width and peak value of the pulse. The
histograms operation is independent of the data collection mode.
The number of histogram bins are listed in Table 4 . The histogram bins are represented by a 20-bit
unsigned number and will saturate at the maximum value (1 048 575). The data is mapped to a bin
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