Hi,
i need to design a low pass filter to filter the pwm signal into DC voltage. Pwm is generated by ATmega64 @ 9MHz (or 16MHz when it's necessary). The pwm should be phase and frequency correct (if it's necessary fast pwm) with resolution 10bit. I calculated the frequency of pwm about 1,1kHz(@9MHz and ph.&fr.co.) but output voltage should be correct at < 5ms. At first time i tried passive low pass filter, but it's too slow. then i tried active lowpassfilter values calculated at http://www.beis.de/Elektronik/Filter/ActiveLPFilter.html but it hasn't good result for me.
My simulation circuit is down...
thanks
excuse my english
i need to design a low pass filter to filter the pwm signal into DC voltage. Pwm is generated by ATmega64 @ 9MHz (or 16MHz when it's necessary). The pwm should be phase and frequency correct (if it's necessary fast pwm) with resolution 10bit. I calculated the frequency of pwm about 1,1kHz(@9MHz and ph.&fr.co.) but output voltage should be correct at < 5ms. At first time i tried passive low pass filter, but it's too slow. then i tried active lowpassfilter values calculated at http://www.beis.de/Elektronik/Filter/ActiveLPFilter.html but it hasn't good result for me.
My simulation circuit is down...
thanks
excuse my english
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