[sdiy] Issue with CD4024 Ripple Counter
Phillip L Harbison
alvitar at xavax.com
Sat Sep 18 14:22:49 CEST 2021
Ingo Debus via Synth-diy wrote:
> In this case, it seems a bit risky to me using chips from one
> manufacturer that worked *so far*, while you know that chips
> from another manufacturer don’t work. At least do some tests
> at different supply voltages and different temperatures.
I agree. If parts from one vendor works but parts from another vendor do
not, it is possible the working parts simply exceed the specification.
Another batch from the same vendor might not work. Depending on parts to
exceed the spec is risky unless you commit to screening parts.
I would check for noise on the clock signal and noise overall. If the
clock has noise, you might consider first passing it through a gate with
a Schmitt trigger. If the clock transition is slow you might consider
passing it through a comparator configured with some hysteresis. This
article has a pretty good discussion of Schmitt trigger and hysteresis.
If you have noise overall consider better decoupling or better ground
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