利用ads1216，ads1217，和ads1218进行温度测量 外文文献译文和原文.doc
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利用ads1216，ads1217，和ads1218进行温度测量 外文文献译文和原文,measuring temperature with the ads1216, ads1217, or ads1218by saeid jannesari and jim todsenoverviewthe ads1216, ads1217, and the ads1218 are integrated systems...
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Measuring Temperature with the ADS1216, ADS1217, or ADS1218
By Saeid Jannesari and Jim Todsen
OVERVIEW
The ADS1216, ADS1217, and the ADS1218 are integrated systems for single-chip high-resolution measurements. Included among the analog features is a diode inside the input MUX. Coupled with the high-resolution Analog-to-Digital Converter (ADC), the diode provides a convenient means of measuring temperature. This application discusses some of the considerations and techniques in using this diode. The last section presents some measurement data to help illustrate the performance that can be expected.
MEASURING TEMPERATURE WITH A DIODE
To understand how to use the diode to measure temperature, it helps to briefly review some of the key equations. For a good, detailed description of the diode’s operation, see The PN Junction Diode by Gerold W. Neudeck. The current through a diode (IDIODE) can be approximated by:
①
where IS is a constant that depends on the area of the diode and its temperature among other things;VDIODE is the forward voltage across the diode, n is a constant usually close to 1, and VT is the thermal voltage given by:
②
where K is Boltzman’s constant, T is the absolute temperature (K) and q is the charge of an electron. Figure 1 shows the typical plot of IDIODE versus VDIODE (the ADS1216’s diode was used in this and all other plots).
利用ADS1216,ADS1217,和ADS1218进行温度测量
作者：Saeid Jannesari and Jim Todsen
综 述
ADS1216,ADS1217,和ADS1218是一种单片集成高精度测温系统。内置的模拟特性一个重要的特点就是多路复用器(MUX)内部集成了一个感温二极管。这个二极管与A/D转换器相连使之提供了一种便捷的测温方式。这篇应用报告主要讨论的就是这只二极管在使用过程中需要注意的事项和技术。最后一节介绍一些测量数据以便于阐述其期望值。
利用二极管测温
要想更好地理解二极管是如何测温的，我们需要复习几个重要的公式。欲了解详细的二极管的工作过程请参考由Gerold W.Neudeck.编写的《The PN Junction Diode》。流过二极管的电流可以近似地表示为：
式（1）
其中，IS是一个常量，其大小取决于二极管的区域以及与其相近的其它器件的温度；VDIODE
是二极管两端的电压，n也是一个常量通常接近于1，VT代表热电势由以下公式给出：
式（2）
其中，K表示玻意尔常数，T表示绝对温度（K）,q表示电荷电量。如图1所示为
By Saeid Jannesari and Jim Todsen
OVERVIEW
The ADS1216, ADS1217, and the ADS1218 are integrated systems for single-chip high-resolution measurements. Included among the analog features is a diode inside the input MUX. Coupled with the high-resolution Analog-to-Digital Converter (ADC), the diode provides a convenient means of measuring temperature. This application discusses some of the considerations and techniques in using this diode. The last section presents some measurement data to help illustrate the performance that can be expected.
MEASURING TEMPERATURE WITH A DIODE
To understand how to use the diode to measure temperature, it helps to briefly review some of the key equations. For a good, detailed description of the diode’s operation, see The PN Junction Diode by Gerold W. Neudeck. The current through a diode (IDIODE) can be approximated by:
①
where IS is a constant that depends on the area of the diode and its temperature among other things;VDIODE is the forward voltage across the diode, n is a constant usually close to 1, and VT is the thermal voltage given by:
②
where K is Boltzman’s constant, T is the absolute temperature (K) and q is the charge of an electron. Figure 1 shows the typical plot of IDIODE versus VDIODE (the ADS1216’s diode was used in this and all other plots).
利用ADS1216,ADS1217,和ADS1218进行温度测量
作者：Saeid Jannesari and Jim Todsen
综 述
ADS1216,ADS1217,和ADS1218是一种单片集成高精度测温系统。内置的模拟特性一个重要的特点就是多路复用器(MUX)内部集成了一个感温二极管。这个二极管与A/D转换器相连使之提供了一种便捷的测温方式。这篇应用报告主要讨论的就是这只二极管在使用过程中需要注意的事项和技术。最后一节介绍一些测量数据以便于阐述其期望值。
利用二极管测温
要想更好地理解二极管是如何测温的，我们需要复习几个重要的公式。欲了解详细的二极管的工作过程请参考由Gerold W.Neudeck.编写的《The PN Junction Diode》。流过二极管的电流可以近似地表示为：
式（1）
其中，IS是一个常量，其大小取决于二极管的区域以及与其相近的其它器件的温度；VDIODE
是二极管两端的电压，n也是一个常量通常接近于1，VT代表热电势由以下公式给出：
式（2）
其中，K表示玻意尔常数，T表示绝对温度（K）,q表示电荷电量。如图1所示为
