1. There is a drop phenomenon during the production process, which means that only the crystal oscillator causes excessive external impact, because the crystal oscillator chip is relatively thin and needs to be handled gently.

2. When the crystal oscillator is soldered to the circuit board, the soldering temperature may be too high and the crystal oscillator may be defective.

3. Virtual welding occurs during the welding process, that is, false welding, so that the crystal oscillator is not energized.

4. After the crystal oscillator is soldered, the solder is connected to the circuit, causing a short circuit.

5. In the leak detection process, that is, under the environment of alcohol pressurization, the quartz crystal resonator is prone to shell collision, that is, the chip and the shell easily collide when vibrating, so that the crystal is likely to vibrate or stop vibrating from time to time;

During compression, the inside of the crystal is required to be evacuated and filled with nitrogen. If the compression is not good, that is, when the sealing of the crystal is not good, under the condition of alcohol pressurization, it will show air leakage, which is called double leakage. Causes to stop vibration.

6. High-frequency crystal oscillator, because the thickness of the chip itself is very thin, when the excitation power is too large, the internal quartz chip will be damaged, causing the oscillation to stop;

7. A functional load will reduce the Q value (that is, the quality factor), thereby reducing the stability of the crystal, which is easily affected by the surrounding active components, and is in an unstable state.

8. Because the crystal is prone to mechanical stress and thermal stress when cutting the feet and soldering, and the solder temperature is too high and the action time is too long will affect the crystal, and it is easy to cause the crystal to be in a critical state, and even the phenomenon of vibration and lack of vibration occurs. Stop vibration

9. When the crystal frequency has a frequency drift and exceeds the deviation range of the quartz crystal oscillator too much, so that the center frequency of the crystal cannot be captured, which causes the chip to fail to vibrate