MAX31855
Cold-Junction Compensated
Thermocouple-to-Digital Converter
General Description
The MAX31855 performs cold-junction compensation
and digitizes the signal from a K-, J-, N-, T-, S-, R-, or
E-type thermocouple. The data is output in a signed
14-bit, SPI-compatible, read-only format. This converter
resolves temperatures to 0.25°C, allows readings as
high as +1800°C and as low as -270°C, and exhibits
thermocouple accuracy of ±2°C for temperatures ranging
from -200°C to +700°C for K-type thermocouples. For full
range accuracies and other thermocouple types, see the
Thermal Characteristics specifications.
Applications
●● Industrial
●● Appliances
●● HVAC
Typical Application Circuit
Benefits and Features
●● Integration Reduces Design Time and Lowers
System Cost
• 14-Bit, 0.25°C Resolution Converter
• Integrated Cold-Junction Compensation
• Versions Available for Most Common Thermocouple
Types: K-, J-, N-, T-, S-, R-, and E-Type
• Detects Thermocouple Shorts to GND or VCC
• Detects Open Thermocouple
●● Interfaces to Most Microcontrollers
• Simple SPI-Compatible Interface (Read-Only)
Ordering Information appears at end of data sheet.
For related parts and recommended products to use with this part, refer
to www.maximintegrated.com/MAX31855.related.
VCC
0.1µF
MAX31855
GND
T+
T-
SO
SCK
CS
MICROCONTROLLER
MISO
SCK
SS
19-5793; Rev 5; 1/15
