Specifications for the Time-to-Digital Converter Histogramming Unit

Sampling interval:
  • 2ns, 4ns, 8ns, or 16ns nominal, software selectable
Timing accuracy:
  • 50ppm at 25°C, or one sampling interval, whichever is greatest
Minimum pulse spacing:
  • 2ns or one sampling interval, whichever is greatest
Data loss rate:
  • zero (subject to overflow criteria below)
Overflow criteria:
  • Burst rate:-
    16 detections in each of up to 64 consecutive frames, each frame being 16 sampling periods long (e.g. up to 1024 hits in 2µs).
  • Mean rate:-
    1 detection per 100ns sampling intervals indefinitely (worst case)
Dead time between cycles:
  • 144 sampling periods
Time window limits (in steps of 256 sample intervals):
  • Suppress time:-
    Up to cycle time minus 256 sample intervals.
  • Cycle time:-
    Up to 32k sample intervals.
Trigger Pulse:
  • Internally generated from external trigger source.
Cycles per experiment:
  • Unlimited, with up to 224 per computer start instruction
Histogram length:
  • 32k bins
Histogram height:
  • 16 bit (wrap on overflow) on board; standard software collects to 32 bits
Power supply:
  • 110-240v AC 50-60Hz
Trigger and signal inputs:
  • User hardware selectable: ECL terminated 50 ohms to -2V, or TTL terminated 50 ohms to groung. NIM/TTL option. (±5v outputs available for pre-amp) +ve or -ve edges.
Trigger output:
  • TTL positive edge
Optional PC interface:
  • ISA bus card/PCMCIA adaptor, or alternative USB option.
Optional IBM PC software:
  • Multiple experiment with summation to 32 bits to give GRAMS/AI compatible data file (Software can be supplied to allow the TDC to operate directly from GRAMS/AI

  • "C" libraries for full TDC control.

  • Source provided to supplement documentation.

TDC housing:
  • 11 x 11.5 x 2.5 inch bench unit with connections at rear LED indicators for Power, Overflow, Reset and Measurement in progress (MIP)

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Last updated: Thursday, September 15, 2005, 11:55

© Kore Technology Limited 2005