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Hot!Xpress board PIC18F46K42: can it be used "Target powered"?

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oliverb
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2018/12/10 02:42:47 (permalink)
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Xpress board PIC18F46K42: can it be used "Target powered"?

So I'm looking at the board and currently it is "blobbed" to 3.3V operation, but it looks like there's another spot for 5V operation. As far as I'm aware it is the 5V compatible version of the PIC not the low voltage one so presumably I could change it to 5V?
 
Can I use it in a circuit that provides its own 5V supply, by opening the connection between the target PIC and voltage regulator. The only problem I can see is that without the USB lead connected MCLR would probably get dragged down meaning the PIC could only run with USB connected.
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    DeutcheN
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    Re: Xpress board PIC18F46K42: can it be used "Target powered"? 2018/12/11 14:27:34 (permalink)
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    There is no harm in removing the "blob" from the 3V point and "blobbing" the 5V.  The device should run fine. 
     
     
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    oliverb
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    Re: Xpress board PIC18F46K42: can it be used "Target powered"? 2018/12/14 11:37:11 (permalink)
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    Thanks, I was also wondering about removing both blobs, and connecting the board to a circuit that provides its own 5v rail.
     
    Update:
     
    So far I've "re-blobbed" it to 5v, and added a header to fit a 40 pin socket so it can be plugged into an old EasyPIC4 I have. That gives me port LEDS and some peripherals. Currently I'm letting the 5V from the USB power the EP4 board.
     
    To adapt it to DIP40 I cut a piece of stripboard the width of the Xpress board, divided the tracks, and soldered on a 40 way header with the smallest bumps I could manage, then I put the Xpress PCB on top and solder-bridged from the pads on the Xpress to the strips on the stripboard
     
    post edited by oliverb - 2019/05/12 08:37:36
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