Instructables

Make your own In-circuit programming board for the Pickit 3

Picture of make your own In-circuit programming board for the Pickit 3

Now, all the cool kids on the block go on and on about Arduino. Arduino this and Arduino that, but there are other alternatives - sometimes faster, more solid, more controllable analog channels, and definitely more sexy options when you are deciding the suit, vest and tie. Plus, who wants to go mainstream, right?

Enter stage left the PIC.

Having the chops to bypass other's bootloaders and such can give you other assets, in the long run. Yes, there is an initial upfront cost in heave-ho to this, but isn't that what DYI really means...?

I drafted, experimented, and finally produced this at Techshop!

 
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Step 1: Set up a regulated de-coupled power supply

Picture of Set up a regulated de-coupled power supply
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Dont mess with volts, I tell you. You will never win. And in this case, we need to get from the 9, the battery, all the way down to 3.3 or so. Just look at the data sheet (page 1) which says our 24F16 chip can't tolerate more than 3.8 volts.

So lets bring in a 1117 3.3 voltage regulator.

IMPORTANT NOTE; do not mix up the pin labels in the schematic with that of the actual physical pins! things will get too hot too soon... this is all in the data sheet for the LM117.

Pin 1 goes to ground

Pin 2 supplies the whole board with 3.3 volts.

Pin 3 is the raw 9 volts coming from the battery.

This is great but we need to smooth it out, since any spikes of power could create havoc. We do this by using capacitors to keep the Current Continuously Consistent. The three big C's. Thats what decoupling essentially boils down to (at least for us).

With this pair, we get a smooth sail throughout the whole board. With this setup, I found a 10uF cap on power in and power out pins works wonders. Now these are polarized, so make sure the back strip leg always heads towards ground.

Now its time to check the current supply for the whole board. If there are any issues, best we work them out before adding (and, perhaps, frying) our microcontroller. The reading should be somewhere around 3.3 volts.