Maxim Integrated MAXREFDES42# IO-Link temperature sensor reference design

The MAXREFDES42# IO-Link temperature sensor reference design (RD), from Maxim Integrated, is a resistance temperature detector (RTD) for industrial control and automation. The design’s highly integrated analog front end (AFE) measures temperature while detecting overvoltage, shorts and open circuits.

The reference design consumes minimal power and is said to provide better than ±.5°C accuracy. The temperature appears immediately on an LED display for a quick snapshot of coarse temperature values.

The product fits in a standard industrial form factor and supports all three IO-Link speeds. It is available for use with a 2-, 3- or 4-wire PT100 RTD over a wide temperature range. Applications include air, gas and liquid temperature measurement.

The configuration software for the temperature detector was developed in collaboration with IQ² Development. The MAXREFDES42# uses an IO-Link device stack to communicate with any IO-Link version 1.1-compliant master. This software control enables fast set-up, diagnosis, event monitoring and maintenance from a PC, without a trip to the installation site.

During operation over a temperature range of -40 to 150°C, the system consumes less than 300 mW of power by utilising an industrial DC-DC step-down converter. Integrated into the front end is the MAX31865 RTD-to-digital converter, which provides flexibility, robustness and optimal performance for an IO-Link platform.