MAX31855SASA+

Sensor And Detector Interfaces Overview

The MAX31855SASA+ is a cold-junction compensated thermocouple-to-digital converter optimized for S-type thermocouples. It digitizes signals from K, J, N, T, S, R, or E-type sensors into a signed 14-bit SPI-compatible read-only format. The device resolves temperatures to 0.25°C, supporting readings up to +1800°C and down to -270°C. For S-type thermocouples, it maintains ±2°C accuracy between -50°C and +700°C. Operating on a 3.0V to 3.6V supply with 900µA typical current, it integrates fault detection for shorts to VCC/GND or open circuits. It operates within a -40°C to +125°C range in an 8-SOIC package.

Sensor And Detector Interfaces Feature Summary

• Integrated cold-junction compensation eliminates external sensor requirements
• Detects thermocouple faults including shorts to power/ground and open circuits
• Read-only SPI interface simplifies microcontroller integration

Sensor And Detector Interfaces Applications

• Industrial process control systems
• HVAC temperature monitoring
• Appliance thermal management

Sensor And Detector Interfaces Procurement Notes

Verify the specific suffix 'SASA+' confirms the S-type thermocouple optimization and SOIC-8 surface-mount packaging. Confirm RoHS compliance status matches project requirements. Ensure the ordering quantity aligns with standard tape-and-reel or tube configurations provided by the distributor. Cross-reference the manufacturer's latest datasheet revision to confirm pinout and electrical specifications remain unchanged.

Sensor And Detector Interfaces Selection Notes

Select this component when interfacing specifically with S-type platinum/rhodium thermocouples requiring high-temperature stability. Verify that the system voltage remains within the 3.0V to 3.6V operational window. Consider the 14-bit resolution and 0.25°C step size against application precision needs. Evaluate the need for integrated fault detection versus external circuitry to reduce bill of materials complexity.

Sensor And Detector Interfaces Part Context

This part belongs to the MAX31855 family of cold-junction compensated converters. Variants exist for other common thermocouple types including K, J, N, T, E, and R. All variants share identical pinouts, interfaces, and core functionality, differing only in internal calibration tables optimized for specific thermoelectric sensitivities.

Sensor And Detector Interfaces Replacement Considerations

MAX31855KASA+ (K-type), MAX31855JASA+ (J-type), MAX31855NASA+ (N-type), MAX31855TASA+ (T-type), MAX31855EASA+ (E-type), MAX31855RASA+ (R-type). These parts are functionally compatible regarding interface and packaging but require different thermocouple types.

Sensor And Detector Interfaces FAQ

What is the maximum measurable temperature for the S-type variant?

The MAX31855SASA+ supports thermocouple measurements up to +1800°C.

How does the device handle thermocouple wiring faults?

It detects shorts to VCC, shorts to GND, and open circuits, flagging these conditions via specific bits in the serial output data.

Is the serial interface bidirectional?

No, the MAX31855 features a read-only SPI-compatible interface; data is transmitted solely from the SO pin to the microcontroller.