Custom USB wiring

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turtle9er

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Hi,

I have a project where in need to use a USB-B receptacle due to it being plugged in and out often. I am making a custom pcb and was wondering if I should route the power from the new USB to Vin or VUSB. On the schematic it would seem to indicate that I could use either, however how can I wire it to utilize the 500mA polyfuse.
While on discussion of USB, on the schematic the micro usb has 5 pins, with one going to the mini54, however my new connector only has 4 pins. Going to assume this will be fine since threads discussing how to fix ripped off usb plugs only show the 4 main wires, however just want to make sure everything will be fine before finalizing my PCB. Thanks.
 
The extra pin is apparently for detecting what sort of cable is plugged in for potential bi-directional use
https://en.wikipedia.org/wiki/USB#Mini_and_Micro_connectors
I don't believe it is actually used by the firmware at the moment.

Going of the Schematic there is no easy way to in series the poly fuse without soldering to it, or the cap. From discussion elsewhere I believe the poly fuse is the small white object with a black mark on it shown on the reference card and connected to the inner V-USB through hole. Your additional wire would go to the other end of it if you want to use it's protection. A better solution may be to supply your own poly fuse as part of your larger PCB since that will protect all components.
 
You make a good point. Guess i can just add my own fuse. Via digikey the only package I can find is a pretty large 2920, but guess I can try to fit it in. Thanks again for the help.
 
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