PIC VPP 13v how much current?

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I chose mine to match the ICD2 adapter cable & the ICD2 clone on ebay (not a good clone; uses the 16F877A so needs a modded bootloader)

I think 13v is so popular because of the 0.7v drop across a typical VPP transistor. 12.3v VPP, and it even works with the 18F series.
 
Not an issue with MOSFET drivers, but an understandable design consideration (bibolar transistors are much cheaper than P-channel MOSFETs).
 
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Mike said:
BTW, did you happen to notice that a VPP voltage of 12v seems to cover more PIC devices than a VPP voltage of 13v?
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The reason for the almost universal use of 13V was basically to ensure the devices got switched to programing mode - the spec (back in the old days) called for 12V, but if it was only 11.9V it might not work, far easier to aim for 13V and gain reliability.
 
William At MyBlueRoom said:
Great, that's easy. I can get 1 to 2 ma without effort.
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I think your schematic have a problem.

Voltage from pin which you use on MAX232 is 8.6V, you use 2 elec-caps and 2 diodes. Vpp generated by that circuit is about 16V - Its too high.
You can use a regulator such as LM317, (resistor: 1K and 220 on ADJ) to generate 13V.
 
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