温度传感器毕业论文中英文资料外文翻译文献

中英文资料外文翻译

英文文献原文

Temperature Sensor ICs Simplify Designs

When you set out to select a temperature sensor, you are no longer limited to either an analog output or a digital output device. There is now a broad selection of sensor types, one of which should match your system's needs.

Until recently, all the temperature sensors on the market provided analog outputs. Thermistors, RTDs, and thermocouples were followed by another analog-output device, the silicon temperature sensor. In most applications, unfortunately, these analog-output devices require a comparator, an ADC, or an amplifier at their output to make them useful.

Thus, when higher levels of integration became feasible, temperature sensors with digital interfaces became available. These ICs are sold in a variety of forms, from simple devices that signal when a specific temperature has been exceeded to those that report both remote and local temperatures while providing warnings at programmed temperature settings. The choice now isn't simply between analog-output and digital-output sensors; there is a broad range of sensor types from which to choose.

Classes of Temperature Sensors

Four temperature-sensor types are illustrated in Figure 1. An ideal analog sensor provides an output voltage that is a perfectly linear function of temperature (A). In the digital I/O class of sensor (B), temperature data in the form of multiple 1s and 0s are passed to the microcontroller, often via a serial bus. Along the same bus, data are sent to the temperature sensor from the microcontroller, usually to set the temperature limit at which the alert pin's digital output will trip. Alert interrupts the microcontroller when the temperature limit has been exceeded. This type of device can also provide fan control.

Figure 1. Sensor and IC manufacturers currently offer four classes of temperature sensors.

"Analog-plus" sensors (C) are available with various types of digital outputs. The VOUT versus temperature curve is for an IC whose digital output switches when a specific temperature