Hi. I'm playing with the thermocouple IC AD595CDZ and am planning on making a PCB shield for my Arduino Mega2560. I'm using a 1000 ohm platinum RTD.
However, I have it plugged up on a breadboard to test it, (hooked up just like Figure 1 on pg 3 of the datasheet, with 12VDC input power), and I'm getting readings at my Arduino, and they are changing with temperature increase/decrease, but they are drastically off, from the table provided in the data sheet. When i look for the reading to equal my ambient temperature (around 77 degrees) the readings associated with that are around 120F.
I thought that adding a 1M resistor to ground from the thermocouple could change the readings but that did nothing,...matter fact it stopped reading/changing with temperature.
Am I doing something wrong from a hardware perspective? Or should I be modifying software equations to compensate for difference? This is the only solution i can think of, but not sure if that's appropriate approach.
thank you for your time.