Hi It is years since I dabbled in electronics. I need a J K Flip Flop (4000 series) J=K=1 Toggles on clock pulse (positive or negative). J=K=0 No change. I thought all JKs did this but 4027 truth table is strange.
Help with logic truth tables
Jan 05, 2012
5 Replies
Que? This one is exactly as per your description.
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Or are you saying that the actual device isn't behaving in accordance with the truth table? In that case, the problem could be unterminated pins, supply rail noise or contact bounce on an input.
Download one of the free spice simulation packages and have a play.
He's expecting the thing to toggle on either edge of the clock, not a standard thing. Datasheet says it flips on rising clock edge only.
Perhaps try an xor with RC to one input, to make a clock pulse ___/\___ from each incoming edge?
Grant.
He said positive OR negative, not positive AND negative. I don't think he meant both, eh?
Then there are those who understand digital and those that don't.
It might be better if the Original Poster explains what the requirement is, rather than persist trying to make a flawed implementation work.
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