原标题：Linear LTC2983精密数字温度测量系统方案

　　Linear公司的LTC2983是多个传感器高精度数字温度测量系统,测量精度℃或°F,精度0.1℃ ,分辨率0.001℃,单电源2.85V-5.25V工作,主要用于温度直接测量,RTD直接测量, 电热调节器直接测量和定制传感器应用.本文介绍了LTC2983主要特性,功能框图,应用电路以及演示板DC2296A主要特性,电路图和材料清单.

　　Multi-Sensor High Accuracy Digital Temperature Measurement System

　　The LTC2983 measures a wide variety of temperature sensors and digitally outputs the result, in ℃ or °F, with 0.1℃ accuracy and 0.001℃ resolution. The LTC2983 can measure the temperature of virtually all standard (type B,E, J, K, N, S, R, T) or custom thermocouples, automatically compensate for cold junction temperatures and linearize the results. The device can also measure temperature with standard 2-, 3-, or 4-wire RTDs, thermistors, and diodes.

　　It has 20 reconfigurable analog inputs enabling many sensor connections and configuration options. The LTC2983 includes excitation current sources and fault detection circuitry appropriate for each type of temperature sensor.

　　The LTC2983 allows direct interfacing to ground referenced sensors without the need for level shifters, negative supply voltages, or external amplifiers. All signals are buffered and simultaneously digitized with three high accuracy, 24-bit ΔΣ ADC’s, driven by an internal 10ppm/℃ (maximum) reference.

　　LTC2983主要特性:

　　Directly Digitize RTDs, Thermocouples, Thermistors, and Diodes

　　Single 2.85V to 5.25V Supply

　　Results Reported in ℃ or °F

　　20 Flexible Inputs Allow Interchanging Sensors

　　Automatic Thermocouple Cold Junction Compensation

　　Built-In Standard and User-Programmable Coefficients for Thermocouples, RTDs and Thermistors

　　Configurable 2-, 3-, or 4-Wire RTD Configurations

　　Measures Negative Thermocouple Voltages

　　Automatic Burn Out, Short-Circuit and Fault Detection

　　Buffered Inputs Allow External Protection

　　Simultaneous 50Hz/60Hz Rejection

　　Includes 10ppm/℃ (max) Reference (I-Grade)

　　LTC2983应用:

　　Direct Thermocouple Measurements

　　Direct RTD Measurements

　　Direct Thermistor Measurements

　　Custom Sensor Applications

　　图1. LTC2983框图

　　图2. LTC2983带冷端自动补偿的热电耦测量电路图

　　图3. LTC2983典型热电耦应用框图

　　图4. LTC2983典型RTD/电热调节器应用框图

　　LTC2983演示板DC2296A(LTC2983主板(DC2209)+20输入分接板(DC2210)

　　The DC2296 is the starter kit for demonstrating the performance and ease of use of the LTC®2983, which is a complete temperature measurement system on a chip.

　　This kit includes the DC2209 (main demo circuit containing the LTC2983) and the DC2210 (a simple experiment circuit allowing bread boarding). In addition to the starter demonstration kit, sensor specific demonstration boards highlighting the performance of RTDs, thermistors, or thermocouples are also available.

　　• Universal Temperature Measurement Board – DC2211

　　• Thermocouple Board – DC2212

　　• Dedicated RTD Board – DC2213

　　• Dedicated Thermistor Board – DC2214 L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and QuikEval and Linduino are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.

　　The DC2209 is a member of the QuikEval™ family of demonstration boards. It is designed to allow easy evaluation of the LTC2983 and may be connected to any one of the sensor daughter boards.

　　These daughter boards allow evaluation of the various LTC2983 sensor types.

　　The DC2296 is the starter kit for demonstrating the performance and ease of use of the LTC®2983, which is a complete temperature measurement system on a chip. This kit includes the DC2209 (main demo circuit containing the LTC2983) and the DC2210 (a simple experiment circuit allowing bread boarding). In addition to the starter emonstration kit, sensor specific demonstration boards highlighting the performance of RTDs, thermistors, or thermocouples are also available.

　　图6.DC2209温度测量演示板系列产品

　　数字温度测量系统材料清单: