Python & CircuitPython

It's easy to use the AD8495 sensor with CircuitPython. This board does not require a separate library. The built in analogio module lets you easily read voltage from a thermocouple and use a simple equation to turn it into temperature.

Raspberry Pi does not have analog inputs, and therefore does not work with this breakout. Consider an I2C or SPI thermocouple amplifier if your project involves Raspberry Pi!

CircuitPython Microcontroller Wiring

First, wire up your AD8495. Here is an example of it wired up to a Feather M0:

  • Board V+ to Feather 3V
  • Board GND to Feather GND
  • Board OUT to Feather A1
  • Board RED- to thermocouple red- wire
  • Board YLW+ to thermocouple yellow+ wire

CircuitPython Usage

To demonstrate use of this board, we'll initialise it and read the voltage and use the equation to turn it into temperature using the board's Python REPL.

First, run the following code to import the necessary modules and initialise the board on pin A1:

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import board
import analogio
ad8495 = analogio.AnalogIn(board.A1)

Next, we'll need a helper function to take the raw data from the thermocouple and turn it into voltage.

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def get_voltage(pin):
    return (pin.value * 3.3) / 65536

Next, we set temperature equal to the equation necessary to convert the voltage from the thermocouple into temperature, using the get_voltage helper.

The equation is (voltage - 1.25) / 0.005.

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temperature = (get_voltage(ad8495) - 1.25) / 0.005

Now we can print the current temperature in C.

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print(temperature)

That's all there is to using the AD8495 with CircuitPython!

Full Example Code

import time
import analogio
import board

ad8495 = analogio.AnalogIn(board.A1)


def get_voltage(pin):
    return (pin.value * 3.3) / 65536


while True:
    temperature = (get_voltage(ad8495) - 1.25) / 0.005
    print(temperature)
    print(get_voltage(ad8495))
    time.sleep(0.5)
This guide was first published on Apr 17, 2019. It was last updated on Apr 17, 2019. This page (Python & CircuitPython) was last updated on Dec 05, 2019.