Comfort 9: Is It Too Hot

Last week I was recommeded to try Differential ADC for measuring temperature (also use NTC). For a future reference, differential ADC means: A differential ADC (Analog-to-Digital Converter) resistor typically refers to the resistors used in a differential ADC circuit, where the ADC measures the difference between two input signals


The issue was ESP32C3 cannot read Differential ADC directly, and at office hour Anthony helped me to come up with a few options:
1. IR Camera to measure IR
2. Differential ADC with a breakout board with a different microcontroller
3. Differential ADC + ESP32C3 with an extra component (Op amp)

Anthony suggested ADC would be the most reliable, so he helped me to understand how differential ADC would play out in a schematic diagram. The diamond diagram in the picture is called "wheatstone."

With the op-amp option, this is the part that will be attached after the wheatstone to make the measurement more readable.

This is how the schematic looked like after all the op-amp + differential ADC + heating pad were added to the schematic diagram.

Quentin suggested to add Mosfet to the heating pad.

I had a bit of issue trying to figure out how to put wires for PCB design. Quentin also helped with figuring out how to connect things without having to make wires go on the other side of the board.
I played around with the wires and put it on a circle shape to match the shape of the heating pads.

PNG files for milling