didn't know where to put this topic
i want to build a lfo oscillator from 2-NAND CMOS 4093
i can find anywhere equation for calculating the R and C for certain frequency
any help?!
i want to build a lfo oscillator from 2-NAND CMOS 4093
i can find anywhere equation for calculating the R and C for certain frequency
any help?!
That doesn't provide much information.
We still need to know the circuit, as that determines the formula.
We still need to know the circuit, as that determines the formula.
You're looking for an astable circuit with 4093 ??
An externally hosted image should be here but it was not working when we last tested it.
The circuit in post 6 is a relaxation oscillator.
The classic astable multivibrator uses two normal gates or two transistors.
Which circuit are you using? You still haven't shown us. No circuit = no formula.
The classic astable multivibrator uses two normal gates or two transistors.
Which circuit are you using? You still haven't shown us. No circuit = no formula.
the digital gate switching thresholds aren't well controlled, speced - the equation just gets you in the ballpark - you have to trim for any accuracy whatsoever
the 555 timer circuit chip has much tighter thresholds - can buy CMOS version too
the 555 timer circuit chip has much tighter thresholds - can buy CMOS version too
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On the other hand, the three component circuit in post #6 can be knocked out on a breadboard in a few seconds and find out.
Find the "CMOS Cookbook" somewhere. It might even be scanned at this point. Yes the book is from long ago, but CMOS basics are basics, and it covers oscillators.
Having said that, I don't know that the relaxation oscillator is the best choice for something slow like an LFO.
Find the "CMOS Cookbook" somewhere. It might even be scanned at this point. Yes the book is from long ago, but CMOS basics are basics, and it covers oscillators.
Having said that, I don't know that the relaxation oscillator is the best choice for something slow like an LFO.
Totally agree with you. I just posted an example in post # 6.
Now, circuit with two logic gates:
got it!
0.59/(R*C) test it with multisim it was pretty close
i dont know for sure why the 0.59 but it works
0.59/(R*C) test it with multisim it was pretty close
i dont know for sure why the 0.59 but it works
The 0.59 comes from circuit theory, as does the RC. Every RC based oscillator will have a period calculated from the RC product, but the associated number depends on the circuit details which is why your original question could not be answered until you told us which circuit you want to use.
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