What should I do if the frequency deviation of the crystal oscillator is too large? 

There are two types of crystal oscillator application solutions: active crystal oscillator solutions and passive crystal oscillator solutions.

Active crystal oscillator:

If the frequency deviation of the active crystal oscillator is too large, please choose an active crystal oscillator with higher frequency accuracy. At the same time, pay attention to the frequency stability of the crystal oscillator within the operating temperature range, which is generally clearly indicated in the crystal oscillator specifications.

Passive crystal oscillator:

Please pay attention to the operating temperature range of the crystal oscillator and its frequency stability within this range.

If the frequency deviation of the passive crystal oscillator is too large, it is recommended as follows.

If the phenomenon of excessive frequency deviation of crystal oscillator occurs at room temperature:

    1. Please confirm if the crystal oscillator load capacitor CL is selected correctly;

    2. Please choose a higher precision crystal oscillator;

    3. Please confirm if the external capacitor of the crystal oscillator is selected correctly;

    4. Please make minor adjustments to the external capacitance of the crystal oscillator. If the external capacitance is raised, the output frequency of the crystal oscillator will decrease, while if the external capacitance is lowered, the output frequency of the crystal oscillator will increase.

    5. Optimize circuit design to reduce interference from stray capacitors on the circuit board to the crystal oscillator;

    6. Suggest an active crystal oscillator solution.

If the phenomenon of excessive frequency deviation of crystal oscillator occurs at low or high temperatures, it is recommended as follows:

    1. Please select a wide temperature crystal oscillator that meets the requirements of the working temperature range;

    2. Please conduct high and low temperature tests on defective crystal oscillators to check whether the frequency temperature curve is abnormal, whether the SPDB, resistance, and DLD indicators meet the standards, etc.