Gage CompuScope 14100C, Hardware Manual And Driver Installation Manual

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148 CompuScope 1610C
CompuScope 1610C External Clock
External clocking is a very powerful feature in a digitizer. It allows the user to synchronize the digitizer to an
external system.
It is important to note, however, that the external clock for CompuScope 1610C must be 2 times faster than the
required sample rate, i.e. if 8 MS/s sampling is required, the external clock must be 16 MHz.
A corollary to this is that the “sampling clock” will always be a divide-by-2 of the external clock.
The External Clock must be a TTL signal (0 to +5 Volts) with a maximum frequency of 20 MHz and minimum
frequency of 2 kHz.
The rise and fall times of the clock signal must be better than 8 ns for proper operation at the peak sample rates.
A minimum pulse width of 22.5 ns must be respected.
In other words, the duty cycle of the clock must be between 50% and 55%.