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We're happy to introduce an excellent analog-output amplifier. This is a very simple sensor to use, and if your microcontroller has analog input capability, you'll be ready to go really fast! Power the board with 3-18VDC and measure the output voltage on the OUT pin. You can easily convert the...
You can build one with separate components, like in this article, but it still uses a dedicated thermocouple-related device:
A Thermocouple is a terrific way to measure temperature. The effects of temperature change on dissimilar metals produces a measurable voltage. But to make that measurement you need an amplifier cir…
Note that every connection from a thermocouple through to it's conditioning circuit is critical.
A thermocouple is just two different metal conductors clamped or welded together, pretty much the same as many basic electrical connectors.
You need to use the matching Type K connectors and extension cable if the built-in cable is not long enough, and make sure any other connections or joints are identical construction (so adding the same offset voltages) in both wires, like where the thermocouple cable connects to the amplifier.
The amplifier output (and ground) can connect directly to the ADC input, if it has suitable gain.
The module in the first link has its output levels printed on the back; 1.25V offset at 0'C [LO] and 5mV per 'C scaling, making 500mV over 100'C, 1.75V out at 100'C [HI]
Convert those to the ADC count at whatever ADC ref voltage is in use, and plug them in the calculation I gave before.
eg. With 2.5V ref, 1.25 / (2.5 / 1023) for LO and 1.75 / (2.5 / 1023) for HI; 512 and 716
[A ten bit ADC has a range of 1024 values, 0 to 1023 inclusive].