Re: capacitor value for VUSB
I know this is an old thread, but it's still a good place to keep this subject.
The datasheet for the 18F4550 says 220nF, but all the schematics I see use 470nF.
Is there a reason why a lot of people use double the rating?
Robert
Re: capacitor value for VUSB
Hi Robert,
The data sheet (page 383) says that 220 is the minimum, but 470 is "typical" or recommended. Max is 12 uF, so you have some range. Usually manufacturers don't put on the bare minimum.
Re: capacitor value for VUSB
Thanks!
I finally found the exact values in the DC Characteristics on page 385 table 28-5 (in my version), the 220nF I found earlier was from within the USB section.
It's comforting to find something more detailed. At least now I know why everyone is using the "typical" 470 when the section I was reading said only 220. I wanted to order caps but wanted to know exactly where I was going first.
Robert
Re: capacitor value for VUSB
Quote:
Originally Posted by
Demon
I finally found the exact values in the DC Characteristics on page 385 table 28-5 (in my version)
:) which is page 383 as printed on the page, but 385 on the adobe index. Would be nice if the two matched! :)