Datasheet

1300 Henley Court

Pullman, WA 99163

509.334.6306

www.digilentinc.com

PmodTC1™ Board Reference Manual

Revised April 12, 2016

This manual applies to the PmodTC1 rev. A

DOC#: 502-315

Other product and company names mentioned may be trademarks of their respective owners.

Page 1 of 3

Overview

The Digilent PmodTC1 is a cold-junction thermocouple-to-digital converter module designed for a classic K-Type

thermocouple wire. With Maxim Integrated's MAX31855, this module reports the measured temperature in 14-

bits with 0.25°C resolution.

1 Functional Description

The PmodTC1 utilizes a K-Type thermocouple wire to measure a wide range of temperatures. The wire provided

with the PmodTC1 is capable of measuring temperatures ranging from -73

C to 482

C, although the module itself

is capable of measuring temperatures ranging from -270

C up to 1800

A thermocouple wire needs to be attached onto the screw terminal. The polarity of the thermocouple matters,

therefore it is required to have the wires screwed down into the right orientation for accurate temperature

readings. The device measures the difference in temperature between the two ends of the thermocouple, of which

one is the internal temperature and serves as the reference junction. Once a temperature reading is established,

the data passes onto a 14-bit ADC and then passed out through SPI.

The PmodTC1.

 K-type thermocouple-to-digital converter

 Wide temperature range of -73°C to 482°C

with provided wire

 ±2°C accuracy from -200°C to 700°C

 14-bit with 0.25°C resolution

 Cold-junction temperature compensation

 Small PCB size for flexible designs 1.0 in ×

0.8 in (2.5 cm × 2.0 cm)

 6-pin Pmod port with SPI interface

 Follows Digilent Pmod Interface

Specification Type 2

 Library and example code available

in resource center

Features include:

PAGE 1
300 Henley Court Pullman, WA 99163 509.334.6306 www.digilentinc.com PmodTC1™ Board Reference Manual Revised April 12, 2016 This manual applies to the PmodTC1 rev. A Overview The Digilent PmodTC1 is a cold-junction thermocouple-to-digital converter module designed for a classic K-Type thermocouple wire. With Maxim Integrated's MAX31855, this module reports the measured temperature in 14bits with 0.25°C resolution. Features include:         The PmodTC1.
PAGE 2
PmodTC1™ Board Reference Manual 2 Interfacing with the Pmod The PmodTC1 communicates with the host board via the SPI protocol. The module sends a variety of information to the host board in 32 clock cycles, including the temperature measured by the thermocouple, the temperature of the “cold junction, as well as signals indicating if there is a fault with the thermocouple. The PmodTC1 uses a 6-pin port to connect to the host board.
PAGE 3
PmodTC1™ Board Reference Manual Table 3 below is the pin mapping of the output pins on the PmodTC1 that connect to a host board. Pin Signal Description 1 CS Active Low Chip Select 2 N/A N/A 3 MISO Serial Data Out 4 SCLK Serial Clock 5 GND Power Supply Ground 6 VCC Power Supply (3.3V) Table 3. Pin mapping of the output pins. 2.1 Figure 1. Block diagram of MAX31855 interfacing with a microcontroller over SPI.