[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.

https://wiki.analog.com/university/courses/alm1k/alm-lab-comp

If you have noise overall consider better decoupling or better ground 
distribution.

-- 
Phil Harbison



More information about the Synth-diy mailing list