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Author Topic: PWM to Analog  (Read 3203 times)

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Offline Iron ManTopic starter

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PWM to Analog
« on: January 27, 2009, 02:37:15 PM »
Can someone point me to a good tutorial on how to convert a PWM to an analog signal?

thanks.

Offline ArcMan

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Re: PWM to Analog
« Reply #1 on: January 27, 2009, 02:44:34 PM »
It's not a tutorial, but the Dimension Engineering Sabertooth drive manual shows you how to do it.  Page 11.

http://www.dimensionengineering.com/datasheets/Sabertooth2x25.pdf

Offline Iron ManTopic starter

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Re: PWM to Analog
« Reply #2 on: January 27, 2009, 02:51:43 PM »
thank you.

Offline Webbot

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Re: PWM to Analog
« Reply #3 on: January 28, 2009, 03:06:59 PM »
You need one resistor and one capacitor to create a low pass filter. The values of these will depend on the PWM frequency vs the frequency of the signal you are generating on top of this. ie you want to filter out the PWM and leave your signal. So your PWM frequency needs to be at least 4 times higher than your signal. Then google for Low Pass RC filer (look on wikipedia) to select values for R and C.

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