Frequency deviation of crystal oscillator and its solution

Feb 21,2025
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Crystal oscillator is a commonly used frequency standard component that plays an important role in electronic circuits. However, in practical use, the frequency of the crystal oscillator is not completely accurate and often has certain deviations. This deviation is caused by various factors, including temperature changes, voltage changes, mechanical stress, and manufacturing deviations.

Generally speaking, the frequency of a crystal oscillator increases with temperature and voltage, and mechanical stress and manufacturing deviations can also cause deviations in the crystal oscillator frequency. In high-speed clock signal lines, the layout of crystal oscillators and the routing of signal lines are also very important. Unreasonable layout and routing can lead to strong stray radiation problems.

To reduce the frequency deviation of the crystal oscillator, the following measures can be taken:

1. Choose high-precision and high stability crystal oscillator components.

2. Control the working temperature and voltage of the crystal oscillator to maintain stable working conditions.

3. Adopt precise mechanical processing and assembly techniques to avoid the influence of mechanical stress on the crystal oscillator.

4. Accurately calibrate the frequency of the crystal oscillator in practical applications to improve its accuracy.

5. The use of temperature compensation circuit is an effective means to solve the frequency deviation caused by the influence of temperature on the crystal oscillator. By adding a temperature sensor to the crystal oscillator circuit, real-time monitoring of the ambient temperature can be achieved. When the temperature changes, the temperature compensation circuit automatically adjusts the oscillation frequency of the crystal oscillator according to a pre-set compensation algorithm to offset the impact of temperature changes on frequency.

In addition to taking measures to reduce deviations, harmonic interference can also be reduced through reasonable layout and routing. The layout of crystal oscillators and CLK signal lines is very important in PCB board layout. The high-speed clock signal line has the highest priority and needs to be routed as briefly as possible to ensure minimal signal distortion. At the same time, try to avoid placing the crystal oscillator near the board edge, equipment casing, and other places to ensure its reliable installation.

In short, frequency deviation of crystal oscillators is an inevitable problem in practical use, but by taking a series of measures, the deviation can be reduced, and the accuracy and stability of crystal oscillators can be improved. Reasonable layout and routing are also important means to reduce harmonic interference in circuit systems.