1. Classification of crystal oscillator
　　Ordinary crystal oscillators can be roughly divided into ceramic crystal oscillators and quartz crystal oscillators. There are also some special crystal oscillators. Such as constant temperature crystal oscillator, temperature compensated crystal oscillator
　　The crystal oscillator is an oscillator that uses a quartz crystal. Its accuracy is very high, and it can generate a very stable frequency, and its thermal stability is better than that of a discrete component oscillator. From the point of view of function, it can be said that the crystal oscillator is the "heartbeat" generator of each board. If the "heartbeat" of a person is disordered, it will be sick. Similarly, if the "heartbeat" of the computer board is disordered, various strange faults will also occur.
　　The crystal oscillator is the most important component in the clock circuit. Its function is to provide the reference frequency for the graphics card, network card, motherboard and other parts of the accessories. It is like a ruler. Unstable working frequency will cause unstable working frequency of related equipment. Naturally Prone to problems. Due to the continuous improvement of the manufacturing process, the important technical indicators such as frequency deviation, temperature stability, aging rate, and tightness of the crystal oscillator are now very good, and it is not prone to failure, but you can still pay attention to the quality of the crystal oscillator when selecting it.
　　Usually, new products of the same model or products with the same volume and parameters are used when replacing the crystal oscillator. In addition, quite a number of circuits have very strict requirements for crystal oscillators. These circuits not only require the frequency of the new crystal oscillator to be the same as the original crystal oscillator, but even the suffix letters must be exactly the same (crystal oscillators are divided into series and parallel), otherwise they cannot It works normally, so everyone should pay more attention when replacing the crystal oscillator, and try to replace the faulty crystal oscillator with exactly the same new product.