Hi, all.
I need to pulse each sensor in a stack of of roughly 1500 sensors. There has to be about 20 microseconds in between pulses, or else my 100khz counter will lose tract. I tried using a LDR that fired a LED... which in turn fired the next LDR and so on. With a small cap in each branch I got this method to work, but LDRs fire way TOO SLOW. Using this method would take 75 seconds to count up all the sensor inputs. I ONLY have 1 second to do this scan. I am COUNTING inputs, NOT timing the whole scan.
I want to try replacing the LDRs with photodiodes in the above circuit. But I am afraid they are TOO fast for my counter to keep tract of. I am not going to go the 555 timer route. I would have to solder in 166 of them.
Any help would be greatly appreciated.
I need to pulse each sensor in a stack of of roughly 1500 sensors. There has to be about 20 microseconds in between pulses, or else my 100khz counter will lose tract. I tried using a LDR that fired a LED... which in turn fired the next LDR and so on. With a small cap in each branch I got this method to work, but LDRs fire way TOO SLOW. Using this method would take 75 seconds to count up all the sensor inputs. I ONLY have 1 second to do this scan. I am COUNTING inputs, NOT timing the whole scan.
I want to try replacing the LDRs with photodiodes in the above circuit. But I am afraid they are TOO fast for my counter to keep tract of. I am not going to go the 555 timer route. I would have to solder in 166 of them.
Any help would be greatly appreciated.
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