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Hi. i am trying to configure a 555 timer to output a 20khz cycle with a 1% duty. I am having trouble because I cant get it to output a lower than 50 % duty cycle with that frequency!
Can you help me calculate the values of r1, r2, and c1?
Thanks a lot.
Manuel
When you aks Google to show you some application notes of the NE555 then you will get something to see how it's done.
By using a diode (or 2) you will get the whole range from 1% till 99%.
look at page 7
http://www.edn.com/contents/images/82202di.pdf
Simple,
Dump the 555.
Get a 12F683.
Then use ...No external parts. No difficult calculations.Code:HPWM 1,2,20000
If desired, add a serial port to set the output with your computer, save the values in EEPROM, then disconnect the computer.
Can't do that with a 555.
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google 555 timer calc and you'll get lots of calculators that will do it for you.Quote:
Originally Posted by manumenzella
yes, as long as they match the extra Diode(s) circuit.
PIC10F???