AC voltage measurement with PIC Micro-controller.

[Thomas Pan]

AC voltage measurement with PIC Microcontroller.

1N4007 470k 10k
0v~300vAC-----------|>|-------^^^--------------^^^---------> To PIC Microcontroller ADC input
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> 3.3k
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GND

[bpislife]

You message makes no sense. If you are reading 0-300VAC, then you will need to rectify that voltage as the negative voltage will destroy the chip. You also need to click the higher voltage down. Since you are using large resistors, and since the PIC uses a charge and hold capacitor, you will need to add a buffer (unity gain op-amp works) to reduce the impedance to less than 2.5Kohm for some pics and 10kohm for others.

Then take a look at the ADC library and the help file.