Nominal Voltage for PIC16F84A'S MCLR PIN
August 6, 2012
I'm designing a PCB for my robot project and I'm having some trouble with MCLR pin. Well, what I'm trying to do is set a jumper in the circuit so that the DC power supply does not interfere with the voltage comming from de serial connector when I'm programing It.
So far I managed to introduce the jumpers in the circuit but MCLR pin gives me a problem. The fact is that this pin acts as the mastereset during reproduction of the program and as a programming pin. So two different currents flow to this pin at different times. I decided to put two diodes (1N4007) so the current flows only in one direction to isolate the programming circuiit form the reset circuit.
So there is a 0.7V decay on each diode. My question is if the diodes would affect the programming or the reproduction of th program.
I attach the schematic so that you have a better view of What I have done.