# Thermocouple Amplifier with 1-Wire Breakout Board - MAX31850K

**Type:** Product page · **SKU:** ADA1727 · **Brand:** [Adafruit](https://core-electronics.com.au/brands/adafruit-australia)
**Page:** https://core-electronics.com.au/thermocouple-amplifier-with-1-wire-breakout-board-max31850k.html ([markdown](https://core-electronics.com.au/thermocouple-amplifier-with-1-wire-breakout-board-max31850k.html.md))

Thermocouples are very sensitive, requiring a good amplifier with a cold-compensation reference. So far Adafruit have carried the very nice MAX31855 which is an SPI interface...

## Pricing

- **Price:** $25.80 (inc GST) — $23.45 AUD, exc GST
- **Quantity discounts:** 10+ $22.75 (exc GST) · 50+ $22.28 (exc GST)

## Availability & dispatch

- Available with a lead time — expect dispatch between Aug 19 and Aug 24.

## Description

Thermocouples are very sensitive, requiring a good amplifier with a cold-compensation reference. [So far Adafruit have carried the very nice MAX31855 which is an SPI interface thermocouple amplifier.](https://core-electronics.com.au/thermocouple-amplifier-max31855-breakout-board-max6675-upgrade-v2-0.html) The '855 is great but if you have a lot of thermocouples to measure it isn't terribly easy to use. That's why Adafruit are also carrying the new '850 model from Maxim - it's a "1-Wire" thermocouple amp which can have any number of breakouts on a single shared I/O line.

The MAX31850K does everything for you, and can be easily interfaced with any microcontroller that has 1-Wire support. This breakout board has the chip itself, a 3.3V regulator with 10uF bypass capacitors all assembled and tested. This board can be used with 'parasitic power' - where the power is on the data line - or with 'local power' where the power for the converter comes in on the Vin Pin.

**Please note: this board does not have level shifting on the 3V Data line** - Adafruit did this on purpose so that it can be used in parasitic mode. The data line must be level shifted to 3V - [Adafruit's 4-channel shifter works wonderfully for level shifting 1-Wire](https://core-electronics.com.au/4-channel-i2c-safe-bi-directional-logic-level-converter-bss138.html) and you only need one at the '1-Wire host' for all thermocouples on the shared data line.

The MAX31850K data format is very similar to that of the well known 1-Wire DS18B20 temp sensor but it is *not drop in compatible* without code changes to check for the new '1 Wire family' type. Adafruit have adapted the classic Arduino [OneWire](https://github.com/adafruit/MAX31850_OneWire) and [DallasTemp](https://github.com/adafruit/MAX31850_DallasTemp) libraries to be MAX31850 compatible, so please click on those links to grab Adafruit's libraries.

Comes with a 2 pin terminal block (for connecting to the thermocouple), 4.7K data line pullup resistor, and pin header (to plug into any breadboard or perfboard). [Goes great with Adafruit's 1m K-type thermocouple](https://core-electronics.com.au/thermocouple-type-k-glass-braid-insulated-k.html). Not for use with any other kind of thermocouple, K type only!

- Works with any K type thermocouple
- Will not work with any other kind of thermocouple other than K type
- **-270°C to +1370°C output in 0.25 degree increments**
- Internal temperature reading
- 3.3 to 5v power supply. Data line is 3V only
- 1-Wire interface allows any number of thermocouple amps on a single data line

Thermocouple Amplifier with 1-Wire Breakout Board - MAX31850K (12:30)

## Technical Details

Dimensions (without headers):20mm x 20mm

[EagleCAD PCB files, Fritzing object, datasheets and more in the tutorial](https://learn.adafruit.com/adafruit-1-wire-thermocouple-amplifier-max31850k/downloads)

 ![](https://core-electronics.com.au/attachments/localcontent/rohs_icon_8216055e11.jpg)

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/1/7/1727-00.jpg)