Hi,
I'm trying to use a 555 timer to produce a PWM waveform however can't find any reference as to how the value of the resistor* can be used to calcuate the duty cycle. Is there a formula that says something like when you use Xohms it gives 2X% duty cycle?
Cheers,
Michael
"Michael" wrote in message news:UY2Bh.331518$ snipped-for-privacy@fe3.news.blueyonder.co.uk...
Bill has a calculator.
Hi,
Thanks, I've put the formula into Excel and everytime I change of the values (R1,R2,C1) it changes both the frequency and duty cycle. Is there a way to change only the duty cycle once you have the frequency you want?
Cheers,
Michael
when
Look to alt.binaries,schematics.electronic for an attached file...
values
"Michael"
** Not possible by varying only one resistor.A pot will do it:
......... Phil
Thanks guys,
Michael
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