Hello, I am trying to use MCP9700 thermometer sensor and relay module in one circuit. I want to check temperature and if it reaches specified level turn on the relay. For the relay I am using this schematic
and for the MCP9700 this:
12 V power supply (xbox power supply) is connected to RAW and GND of the Arduino and JD-VCC and GND of relay module.
The problem is the temperature read is unstable and it depends on relay state. So if the relay is on - the temperature read is about 3 Celsius more than normal (when the relay is off). Is there any way to have stable readings without using additional power supply?