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I recently ran into an issue with USB cable lengths and an FT230XS where I didn't include the 47R and 27pF on the data lines. I'm working on a project now where I use CDC for communication so I have the D+/D- lines going directly to a PIC18F2550. Do I need to include any RC for this situation? I've had some trouble locating answers for this specific situation.

edit: also, for whatever reason, would the 5 pin header for programmer jtag need filtering as well? I haven't used any RC on the programmer jtag before, but if it's the "correct" way to do it I'd like to.

Thanks for the help

coolestDisplayName
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Although it is always recommended to include pull-up resistors for USB lines, the PIC18F2550 already has internal resistors that can be used for this. Please check pages 163 to 167 of the datasheet.

As for the capacitors, I don't find them always necessary, but it doesn't hurt to leave the space for them in case you need them further ahead.

Never seen resistors or capacitors for the JTAG header.

jlhonora
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