Hi all,
I have a print (see attachment) which serves as a trig controller for a machine vision project. The purpose is to output a TTL high whenever S1 and D1 or S2 and D2 are overlapping. S1 and S2 are pulsetrains from a proximity sensor and D1/D2 are used to filter these pulses to output a trig when these overlapps. The issue we are having now is noise on the flip flop clock. The noise is extremely short and approx 2V. The consequence is: The output generates an output when theres noise on the clock -> a clear is neccessary before any valid signal could trig the output.
The obvious solution is to use a filter of some kind at the flip flop clock but this would also filter a valid pulse. Since the valid pulse is a result of a previous filtering (AND of S1/D1 or S2/D2) further filtering would cause problems. D1 and D2 are set by a software, hence the software know the filtering but as soon as we introduce another filtering the software is unaware of this.
I would prefere something like a schmitt trigger where the threshoild is adjustable. Is there anything like that or how would a solve this issue?
BR
Jongas
I have a print (see attachment) which serves as a trig controller for a machine vision project. The purpose is to output a TTL high whenever S1 and D1 or S2 and D2 are overlapping. S1 and S2 are pulsetrains from a proximity sensor and D1/D2 are used to filter these pulses to output a trig when these overlapps. The issue we are having now is noise on the flip flop clock. The noise is extremely short and approx 2V. The consequence is: The output generates an output when theres noise on the clock -> a clear is neccessary before any valid signal could trig the output.
The obvious solution is to use a filter of some kind at the flip flop clock but this would also filter a valid pulse. Since the valid pulse is a result of a previous filtering (AND of S1/D1 or S2/D2) further filtering would cause problems. D1 and D2 are set by a software, hence the software know the filtering but as soon as we introduce another filtering the software is unaware of this.
I would prefere something like a schmitt trigger where the threshoild is adjustable. Is there anything like that or how would a solve this issue?
BR
Jongas
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