High-precision temperature measurement using advanced thermocouples and high-resolution Σ-Δ ADCs

introduction

Thermocouples are widely used in various temperature detection. Recent advances in thermocouple design, as well as the emergence of new standards and algorithms, have greatly expanded operating temperature range and accuracy. Currently, temperature detection can achieve an accuracy of ±0.1°C over a wide range of -270°C to +1750°C. To fully exploit the capabilities of the new thermocouples, a high-resolution thermocouple temperature measurement system is required. Low-noise, 24-bit, sigma-delta analog-to-digital converters (ADCs) capable of resolving extremely small voltages are ideally suited for this task. The data acquisition system (DAS) uses a 24-bit ADC evaluation (EV) board with thermocouples capable of temperature measurement over a wide temperature range. Thermocouples, platinum resistance temperature detectors (PRTD), and ADCs are combined to form a high-performance temperature measurement system. DAS systems using low-cost, low-power ADCs can ideally meet the application needs of portable detection.