Hi All,

Can someone explain why Vpp is connected to Vdd as shown in the ICSP 
diagram at http://kitsrus.com/gif/icsp.gif

The associated page at http://kitsrus.com/icsp.html mentions "The 27K is 
recommended to prevent VPP current from raising VCC" but I don't see how 
this works.

What I figure is that during ICSP when Vpp is applied (13V) shouldn't 
Vcc (5V) be (lightly) pulled up to 13V because of that 27K resistor? 
Wouldn't this then exceed the "Max voltage on Vdd with respect to Vss" 
spec and damage the PIC?

I'm sure I'm missing something here (because I have used this ICSP 
circuit successfully), but I just can't see it ;-/

BTW a related question - is the MCLR pin more susceptible to ESD because 
it doesn't have an internal clamp diode to Vcc?

Thanks in advance,
Kevin
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