I have a thermostats. I want it to turn on a relay at 80 degrees and off at 79 degrees. The relay needs 12volt to turn on and 6volts to turn off. The thermostats only adjust a half volt. Does anybody know how to do this with out a microcontroller? Thanks
Use an LM34, Farenheit to voltage converter and a comparator. The LM34 output is 10mV per deg F and will be 0.8 volts at 80 deg F. There is also an LM35 which is Centigrade to voltage converter.