When I got my first reflow oven, the T-962, I was a bit disappointed with the built-in firmware. After I’ve made the several must do improvement hacks shown here, here and here. I’m still stuck with the badly written firmware and keep scorching many of my boards using the in-built profiles. There is a replacement controller available but it cost almost as much as the oven itself! Besides, the built-in controller has an ARM LPC2134 processor on board, it seems a waste not to make the most out of this 32-bit processor.
I was delighted to found that Mr. Werner Johansson of Unified Engineering has managed to improve the firmware of the T-962 Reflow Oven. His firmware has much enhancement over the original and by adding new thermocouple amplifiers, you can get more consistence results. Mr. Johansson makes use of the MAX31850 thermocouple amplifier from Maxim, which is a One-Wire device. His choice of this amplifier is due to the free pins available on the original controller. However, the MAX31850 comes in TDFN package. For those who has little confident to hand solder a TDFN package, I’ve a less elegant solution here. It does require extra chips and small modifications, but all the chips are available in either SO-8 or TSSOP package which even I can hand solder without any problem.