JDM2 Based PIC Programmer

The project includes clock & data filter and voltage divider for modern PIC microcontroller using an updated JDM2 PIC programmer.

The programmer is using 6 common components along with a PIC16F628 processor although the system is limited to less than 18pin PICs with a programming voltage divider of 13V. There are two enhancements on the JDM2 programmer based circuit which includes clock & data line filtering and selectable programming voltage. Newer PICs are programmed so fast that the clock and data lines can experience crosstalk. Filters were included in the programmer because the data/clock traces are long. The capacitors are situated in this circuit so that they can be excluded without weakening the trace.

To provide 12.5V from the original 123V output, a voltage divider was added to the JDM2 design. Preventing leakage through the voltage divider when it is bypassed is the function of a diode. The three pin jumper sat the programmer are used to select the programming voltage.

The programmer will work with any programming software that supports the JDM2. For future improvements, the design can replace the 28 and 40-pin sockets with one 40-pin ZIF socket with little extra clearance.

Rest of the project