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Time-to-Digital Conversion

It is possible to digitize relatively long time intervals by incrementing a counter with a repetitive signal derived from an oscillator. For short time intervals the time-to-digital converter (TDC) circuit shown in figure 8.8 can be used.

Figure 8.8:  A time-to-digital converter. The circuit is shown with the switches in the signal-holding position after a STOP pulse and with RESET false.

The resulting voltage on the capacitor is proportional to the time between the START and STOP pulses as shown in figure 8.9.

Figure 8.9:  TDC timing signals.

Doug Gingrich
Tue Jul 13 16:55:15 EDT 1999