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Author Topic: PWM dithering explanation  (Read 2801 times)
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During my implementation of software PWM for my project (hardware pwm no option), i stumbled on an interesting algorithm. I have tried to write an explanation on my blog here: http://simplicate.weebly.com/1/post/2013/05/using-bresenham-line-algorithm-for-better-pwm.html

I hope you find it useful. Thank you for your time!
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Rob
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Great minds, etc.

http://forum.arduino.cc/index.php?topic=149369.msg1121850#msg1121850
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Haha indeed! Had i known this, etc. etc.

One of those moments where google failed.
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Rob
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This is called Pulse Density Modulation (PDM) since it is no longer the exact pulse width but the average density of the pulses which conveys the analog value.
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Very interesting. Never thought of that.

Little correction on the article. The flicker frequency " for lack of better words" of 30 is too low. For a TV that's ok as usually pixels are not turned from full on to full off etc.
However PWM dimming does just that so the min frequency that will not be noticed by most people is 100Hz.
« Last Edit: May 20, 2013, 08:33:53 pm by Headroom » Logged


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This is called Pulse Density Modulation (PDM) since it is no longer the exact pulse width but the average density of the pulses which conveys the analog value.
I guessed there was a proper name for it. Thanks.
The flicker frequency " for lack of better words" of 30 is too low. For a TV that's ok as usually pixels are not turned from full on to full off etc.
However PWM dimming does just that so the min frequency that will not be noticed by most people is 100Hz.
Also noted. I'll correct the text!

Thank you both. It's not easy to be correct with so many prying eyes on the web, lol  smiley
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