Two-Wire Galvanically Isolated IC Temperature Sensor Reference Design with Pulse Counting Interface

To provide system designers with a new cost-effective and simple alternative solution for high-precision temperature measurement, this reference design introduces a new ultra-small 2-pin digital output IC temperature sensor with a single line pulse counting interface that improves reliability and greatly simplifies the design of electrically isolated architectures to send power and unidirectional data through the same low-profile transformer and remote operation. Additionally, error budget calculations are simpler because there are fewer error sources. Cost budget, accuracy, size, and simplicity of connection to other circuit components are major factors to consider when selecting a sensor to perform the job, and this reference design system can be of great assistance in meeting these requirements. This design has a maximum measurement error of less than 0.25°C over the -50°C to 150°C temperature range, provides 400VRMS of functional isolation, and is pre-certified to IEC61000-4-4 to significantly reduce the cost of high-accuracy temperature measurement systems Development design time.

characteristic

• ● High-precision 2-pin digital output IC temperature sensor with pulse counting interface
• ● Sensor temperature range: -50ºC to +150ºC, maximum measurement error over the entire temperature range:
  • ● Using LUT: less than 0.25ºC (-35ºC to +150ºC)
  • ● Use first order equation: less than 0.25ºC (+15ºC to +100ºC)
• ● Remote temperature monitoring over 2-wire long links
• ● No special power requirements or the need for traditional bulky single transformers and optocouplers for power and data isolation
• ● Used to replace RTD and NTC/PTC thermistors
• ● No system-level calibration or hardware/software compensation