Project overview: This project will make use of the MAX6675 Cold-Junction-Compensated K-Thermocouple-to-Digital Converter. It basically takes the millivolts produced by a standard K-type thermocouple, amplifies it, and outputs it's temperature reading. This reading is received by a microcontroller, which then displays the reading on an LCD display. This unit will be capable of reading temperatures up 1800 degrees fahrenheit.
The first step in this project was to take the very tiny MAX6675 chip and mount it to a useable sized adaptor chip. This first pic shows the small adaptor board, the tiny chip, and the headers I would solder to the adaptor chip.
This next pic shows everything soldered up into a nice, neat package.
Now that I had the 'main' chip ready to go, I could begin prototyping this circuit. The first step here is to get all my misc. electronics hooked up and ready:
Once that was done, I could begin putting it all together. The first part of the circuit I got working was the LCD display. I needed that working first before I could begin using the thermocouple interface chip.
The second, and last step to this prototype was getting the MAX6675 chip working and displaying the temperature results on the LCD:
Once the blue LCD arrives, I'll be able to test everything with it, then work on getting it all soldered up onto a circuit board.
Good news! The blue LCD finally got here from China and I've already got it working. This pic is slightly fuzzy because I had to turn off the flash on my camera to capture the LCD correctly, but it looks GREAT in person.
Next step: To get it all soldered together on a circuit board.
Okay, the first picture is of the assembly process:
This is the finished unit. The camera flash is turned ON in this pic, causing the LCD to look dark...
This pic is of the finsihed unit, but with the camera flash OFF showing the LCD's true color: