TIGER documentation

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QDC mode[edit | edit source]

Efine with wrap-around effect explained

The counter for the ADC performing the charge digitization has a wrap-around effect such that very high signals (just below the saturation point) have 1008 < Efine < 1024.

For these values the measurement is still linear, so in order to apply the usual conversion using the calibration line (Efine = const + slope * Qin) we need first to shift them by 1024. Therefore we can define a new variable Efine_new given by:

  • Efine_new = Efine (for Efine < 1008)
  • Efine_new = Efine - 1024 (for Efine > 1007)

In this way, the values of Efine between (1008, 1023) are shifted to the region (-16, -1) and thus correspond to the very high charge signals, with Efine_new = -16 being the new value of saturation. This is explained in the Figure on the right and the Table below.

Qin Efine Efine_new Description
5 385 385 normal region
10 340 340 normal region
15 295 295 normal region
20 250 250 normal region
20 205 205 normal region
30 160 160 normal region
35 115 115 normal region
40 70 70 normal region
45 25 25 normal region
46 16 16 normal region
47 7 7 normal region
48 1022 -2 wrap-around region, still linear -> apply Efine_new
49 1013 -11 wrap-around region, still linear -> apply Efine_new
50 1008 -16 saturation
55 1008 -16 saturation
60 1008 -16 saturation


Output words[edit | edit source]

TIGER output words
  • Event word: 64 bits, includes digitized information for each hit
  • Count words: 64 bits, includes information about internal counters
  • Framing word: 64 bits, includes information about frame word used for time reference and SEU count detected for each frame

TIGER padframe[edit | edit source]

TIGER padframe