- Joined
- Jan 21, 2010
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- 25,510
OK, I've just had a quick read of the thread.
My recommendation would be to make a prototype board that has proper connections for your programmer. This will be physically larger than your design target, but will allow you to easily test the unit, reprogram, and replace components as necessary. In addition you might be looking at a single sided board as it is easier when you're testing a bare board.
Another option is breakout boards for the various components and a breadboard.
The three questions I have for you are:
1) Do you have any experience making PC boards?
2) Do you have any experience writing software?
3) Have you ever programmed a microcontroller?
If you have any issues with (1) I can make you a couple of prototype boards and mail them to you. I also have a selection of SO-08 mosfets capable of up to 30A which may be useful if the ones you have prove to be problematic. (e.g. FDS4070N3, and SI4936DY). I also have some PIC10F206's so I may be able to also build a similar prototype and help you debug it.
My recommendation would be to make a prototype board that has proper connections for your programmer. This will be physically larger than your design target, but will allow you to easily test the unit, reprogram, and replace components as necessary. In addition you might be looking at a single sided board as it is easier when you're testing a bare board.
Another option is breakout boards for the various components and a breadboard.
The three questions I have for you are:
1) Do you have any experience making PC boards?
2) Do you have any experience writing software?
3) Have you ever programmed a microcontroller?
If you have any issues with (1) I can make you a couple of prototype boards and mail them to you. I also have a selection of SO-08 mosfets capable of up to 30A which may be useful if the ones you have prove to be problematic. (e.g. FDS4070N3, and SI4936DY). I also have some PIC10F206's so I may be able to also build a similar prototype and help you debug it.
All kidding aside, it is still unknown if this circuit design will even work, so for now all I want is a bare bone program to test the design. The PIC needs to fire the MOSFET momentarily if the switch is pressed <500ms, maintained if pressed >500ms. If the MOSFET is latched on, pressing the switch again will turn it off. This seems simple enough, but the challenge is the fact that all voltage potential across the circuit is lost when the MOSFET turns on, so there is nothing to keep the PIC and gate powered up. Kris's latest idea was to have the PIC switch the MOSFET off for 1 ms every 100 ms, keeping CR charged. These timings may need to be adjusted, as well as the value of CR, but we have a starting point. If the design works, I would like to add a couple more functions to the PIC to take advantage of it being there, but we'll keep it as simple as possible for now.
