Principle and Application of Digital Temperature Sensor
Today, with the rapid advancement of sensor technology, the new digital temperature sensors provided by many modern sensor companies have higher cost performance, superior performance, higher reliability, convenient use, smaller size, higher sensitivity and simple control circuits compared to traditional temperature sensors. Features. Can completely replace the traditional thermistor and resistance temperature detector.
Principle of new digital temperature sensor
The digital temperature sensor is also called a thermocouple. It welds two different materials of conductors or semiconductors A and B to form a closed circuit. When there is a temperature difference between the two attachment points 1 and 2 of the conductors A and B, the two An electromotive force is generated between them, and a large current is formed in the circuit. This phenomenon is called the thermoelectric effect. Thermocouples use this effect to work. Thermocouples are one of the most commonly used temperature sensing elements in the industry. Its advantages are: (1) high measurement accuracy; (2) wide measurement range; (3) simple structure and convenient use.
Application of new digital temperature sensor
The new digital temperature sensor has a wide range of applications. It is not only widely used in ordinary people's daily life, but also widely used in modern industrial production automation control and production process detection control system.
The new digital temperature sensor should pay attention to the following issues in practical applications:
To prevent environmental interference, a tantalum capacitor with a capacitance greater than 0.1 μF should be connected between the power supply and the ground;
The temperature-sensing device is inside the chip, so the surface of the chip needs to be in close contact with the chip; due to the self-power consumption of the chip, the self-temperature rise during operation is about 0.2, so a low-power operation mode should be adopted in accurate temperature measurement;
The larger the pull-up resistance at the output, the smaller the current flowing in and the smaller the temperature rise. However, the maximum pull-up resistance cannot exceed 30kΩ, usually 10kΩ.
Although the new digital temperature sensor has many advantages, in actual application, due to the use of a single bus data transmission method, the timing requirements for read and write operations are strict. Reasonable application of the temperature measurement system constructed by the new type of temperature sensor, with a simple structure Great convenience comes, which can effectively reduce costs and shorten development cycles.