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I have found this tutorial but don't have a 0.1uF Capacitor. I am an amateur when it comes to electronics, but I don't know if I can swap 0.1uF for a 1uf or 1.5uf. Any help would be greatly appreciated.

schematic finished PCBA

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  • \$\begingroup\$ a 1uf capacitor will work, but you may find that some of the high frequency noise, like glitches and spikes are not attenuated as much \$\endgroup\$ – jsotola Apr 1 '18 at 1:53
  • \$\begingroup\$ Can I use an electrolytic capacitor? \$\endgroup\$ – JustAnotherBitcoin Apr 1 '18 at 2:20
  • \$\begingroup\$ Often you will see 100nF caps in parallel with 4.7uF caps and upstream maybe a 47uF cap. The lowest value should have the lowest ESR and be the closest to an IC's power and ground pins. \$\endgroup\$ – Sparky256 Apr 1 '18 at 2:35
  • \$\begingroup\$ The datasheet of the LM2577 or attendant app note will tell you how to load this appropriately with capacitance \$\endgroup\$ – Voltage Spike Apr 1 '18 at 6:27
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A film capacitor has a much higher self resonant frequency (SRF) and hence a lower shunt impedance to suppress impulse noise. You must not substitute an electrolytic cap otherwise it will not perform the same for noise ripple suppression.

Ceramic with high SRF may be used for low voltage and metal film must be used for high voltage such as in IGBT snubbers.

enter image description here

All caps have this property but if the datasheet does not specify the SRF , which varies widely depending on source and family , you can assume it is not a special high SRF component.

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C3 should be a low resistance type: ceramic or metalized film. and yeah using a larger capacitance will not be a problem.

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  • \$\begingroup\$ Could I use electrolytic? \$\endgroup\$ – JustAnotherBitcoin Apr 1 '18 at 2:17
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    \$\begingroup\$ @JustAnotherBitcoin Different capacitor construction will have different frequency responses, so electrolytic may not be ideal. But then different capacitances will have different responses and you've already changed that pretty significantly. Unless whatever you're powering is particularly noise sensitive, you'll probably still be fine. If electrolytic is all you have then give it a shot and see if it works to your needs. \$\endgroup\$ – Phil C Apr 1 '18 at 2:31
  • \$\begingroup\$ electrolytic is not so good, they have a relatively high internal resistance, for low resistance Multi-layer ceramic (MLCC) is the best type, but the photo seems to show metalized film capacitors. these are not are not so good at high frequencies but 52kHz is probably not enough that this would be a problem. as Phil C says it if it's somethins simple like a lamp or a motor it will probably work fine, an audio amplifier might be problematic. \$\endgroup\$ – Jasen Apr 1 '18 at 2:51
  • \$\begingroup\$ It didn't work. I spent 4 hours trying to fix it but the highest voltage it it outputted was 1V but at the end, 0V \$\endgroup\$ – JustAnotherBitcoin Apr 1 '18 at 20:43

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