UroBoros
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Hai,
Sorry if this is a subject already have discussion, (Good chance for that) but I was not able to find answer for my issue with search here.
For my Pic Micro circuits I usually Power from small SMPS and in some cases transformer and bridge. Usually I bring 12v to Board, provide a filter of arounf 1000Uf and Then a 7805 with .1uf at both ends. then close to PIC Power pin I provide 220uF and .1Uf In parallel. and in MCLR I provide 4k7 pull up and .1uF to Gnd. This usually works without much problem.
Now I have to do a PIC Board which will be placed in the proximity of High current motors and brushed grinders etc which can cause noise and spikes in power lines. So I think I need a more robust power supply transient protection and filtering in the power lines. Like to know what will be the best approach in this case.
What comes to my mind is a pi filter with a inductor. I searched and found circuits and and formulas for cut off frequency etc. But what should be the cut off frequency and what should be the core for inductor. Since usually inductor value seems high, then ferrite core may be needed.
Can I get some info without too much calculations but with required basic info to tailor for my needs. My PIC circuits may maximum take below 500mA.
Thanks
Sorry if this is a subject already have discussion, (Good chance for that) but I was not able to find answer for my issue with search here.
For my Pic Micro circuits I usually Power from small SMPS and in some cases transformer and bridge. Usually I bring 12v to Board, provide a filter of arounf 1000Uf and Then a 7805 with .1uf at both ends. then close to PIC Power pin I provide 220uF and .1Uf In parallel. and in MCLR I provide 4k7 pull up and .1uF to Gnd. This usually works without much problem.
Now I have to do a PIC Board which will be placed in the proximity of High current motors and brushed grinders etc which can cause noise and spikes in power lines. So I think I need a more robust power supply transient protection and filtering in the power lines. Like to know what will be the best approach in this case.
What comes to my mind is a pi filter with a inductor. I searched and found circuits and and formulas for cut off frequency etc. But what should be the cut off frequency and what should be the core for inductor. Since usually inductor value seems high, then ferrite core may be needed.
Can I get some info without too much calculations but with required basic info to tailor for my needs. My PIC circuits may maximum take below 500mA.
Thanks