Heated Build Platform Controller V0.2

I really wanted a fully integrated solution for controlling a heated build platform, as well as for communicating with the motherboard. I also wanted to be able to use the heated build platform as a controlled hot plate in order to do surface mount reflow. I created this board to have the ability to do both. I started this several months ago, but just now was able to gather all of the parts to build it and test it.

The board is meant to control mains voltage (i.e. 120/240 VAC), and therefore uses an optically-isolated triac that is protected by a fuse. Temperature feedback is through a Type-K thermocouple being read by a MAX6675. The whole system is controlled by an ATMega328 based Arduino in a TQFP package. Feedback to the user is through a 16x2 LCD and 3 buttons. The control circuitry is powered though the 5V line on a Molex connector off of an ATX power supply.

Features:
*Controls up to 1000W of AC mains power
* I2C Communications back to the motherboard
*Measurable temper