Causes of bad crystal oscillator in the process of use

The author:admin Number of visits: Date:2020-12-28 13:48

The use of crystal oscillator is analyzed as follows:

Beijing Jingyuxing is a professional manufacturer of crystal oscillators.Factory has a good production environment and clean production workshop, all-weather workshop temperature control, also has the first-class technical personnel, advanced production equipment and testing instrument automation, factory semiconductor products after a series of aging rate test of vibration, a few crystals here to teach you simple often appear not vibration.

1, the production process has the phenomenon of big fall, which means that only the crystal oscillator causes the excessive impact force of the outside world, because the crystal oscillator chip is relatively thin, and it needs to be handled gently.

2. When the crystal oscillator is welded to the circuit board, the welding temperature may be too high, resulting in poor crystal oscillator;

3. False welding occurs in the welding process, that is, false welding, so that the crystal oscillator is not electrified;

4. After crystal vibration welding, the solder is connected with the line, resulting in short circuit phenomenon;

5. In the leak detection process, that is, under the pressure of alcohol, the quartz crystal resonator is prone to collision with the shell phenomenon, that is, when the chip is vibrating, it is easy to touch with the shell, so that the crystal is prone to vibration when depressed or stop vibration;

6, in the sealing, the crystal interior requires vacuum filling nitrogen, if the sealing is bad, that is, the crystal sealing is not good, under the condition of alcohol pressure, its performance is leakage, known as double leakage, will also lead to vibration stop;

7, because the thickness of the chip itself is very thin, when the excitation power is too large, the internal quartz chip will be damaged, resulting in vibration stop;

8, functional load will reduce the Q value (that is, the quality factor), so that the stability of the crystal decline, easy to be affected by the surrounding active components, in an unstable state, when the phenomenon of vibration and stagnation;

9, because the crystal in the shear foot and solder is easy to produce mechanical stress and thermal stress, and the solder temperature is too high and the action time is too long will affect the crystal, easy to lead to the crystal in a critical state, and even when the vibration is depressed phenomenon, or even stop vibration;

10. In soldering, when the tin wire penetrates through the hole on the circuit board, leading to the heel shell is connected in a piece, or in the manufacturing process of the crystal, the tin point of the pin on the base and the shell are connected with a single leak, which will cause a short circuit, thus causing the vibration stop;

11. When the frequency drift of the crystal frequency occurs, and the deviation range of the quartz crystal oscillator is too much, so that the central frequency of the crystal can not be captured, which leads to the vibration of the chip.

The above 11 reasons should be controlled as far as possible in the production process.

Treatment method:

In strict accordance with the technical requirements, carry out leak test on quartz crystal components to check their tightness, timely deal with defective products and analyze the reasons;

1. The sealing process is to package the tuned resonator with the shell in the nitrogen protection to stabilize the electrical performance of the quartz crystal resonator.In this process, the feeding silo, the sealing silo and the discharging silo should be kept clean, the sealing silo should be continuously filled with nitrogen, and pay attention to the welding head wear and mold position during the sealing process, and whether the voltage, air pressure and nitrogen flow are normal, otherwise, it should be handled in time.Its quality standard is: no scar, burr, top pit, bent leg, embossing symmetry can not skew.

2, because quartz crystal is a passive component, it is provided by the IC appropriate excitation power and normal work, therefore, when the excitation power is too low, quartz crystal oscillator is not easy to start vibration, too high, it will form overexcitation, so that quartz chip damage, cause vibration stop.Therefore, appropriate excitation power should be provided.In addition, the active load will consume a certain amount of power, thereby reducing the crystal Q value, so that the stability of the crystal decreases, easy to be affected by the surrounding active components, in an unstable state, when the vibration and lack of energy phenomenon, so, plus active load, should match a more appropriate active load.

3. Control the shearing foot and soldering process well, and ensure the insulation performance of the base and the quality of the pins. The pin coating is bright and uniform, no pockmarked surface, no deformation, cracks, discoloration, scratches, stains and coating peeling.To better prevent single leakage, an insulating gasket can be added under the crystal.

4, when the crystal frequency drift and beyond the range of frequency difference, should be checked to match the appropriate load capacitance, can be adjusted by the crystal load capacitance to solve

Beijing Jingyuxing Technology Co., Ltd. has professional engineers of quartz crystal oscillator, if you use the crystal oscillator in the process of bad phenomenon, you can call inquiry at any time, my company will send professional personnel to solve, the production process is all in the strict process, please rest assured that the company produces crystal oscillator series products.