he most fundamental resonant device is a dielectric resonator. To understand how a dielectric resonator works, first understand the metal waveguide and resonator. The designation of a quartz crystal resonator consists of the following three parts.
The first part is to show the shape and material of the shell in a Chinese phonetic alphabet, for example, J is the metal shell, S is the plastic shell, B is the glass shell.
Part 2: The first letter of the crystal cut symbol indicates the type of orientation of the quartz slice. Crystal cutting type and symbol see table. The main characteristics of quartz crystal resonator parameters are nominal frequency, adjust the frequency difference, temperature frequency difference, equivalent resistance, excitation level, load capacitance, static capacitance, aging rate and temperature range.
① Nominal Frequency: The resonant center frequency specified by the resonator under the specified conditions.
② adjust the frequency difference: under the conditions specified, the reference temperature of the operating frequency relative to the maximum deviation of the nominal frequency.
③ temperature frequency difference: under the specified conditions, the entire operating temperature range, relative to the reference temperature when the operating frequency of the allowable deviation value.
(4) Reference temperature: When measuring quartz crystal resonator parameters, the specified ambient temperature. For the constant temperature quartz crystal resonator, the central point of the operating temperature range is generally; for non-constant-type quartz crystal resonator, 25 ℃ ± 2 ℃.
⑤ load resonance resistance: quartz crystal resonator and the specified external capacitor in series, the resonant frequency of the load resistance.
⑥ excitation level: Quartz crystal resonator is the work of the effective power consumption, it is applied to the quartz crystal element of the excitation state of the measurement. Commonly used standard values are 0.1mW, 0.5mW, 1mW, 2mW and 4mW. In actual use, the excitation level can be adjusted, easy to start when the strong excitation, excitation is too weak when the frequency stability of deterioration, or even vibration.
⑦ load capacitance: refers to the quartz resonator with the resonant frequency of the load resonant about the effective external capacitance. Load capacitance commonly used standard values are 16pF, 2OpF, 3OpF, 5OpF and 100pF. Load capacitance can be adjusted according to specific circumstances, by adjusting the resonator frequency can be tuned to the nominal value.
⑧ static capacitance: Quartz crystal resonator static capacitance between the two pins.
⑨ aging rate: refers to the increase with time, quartz crystal aging changes arising from the error, the unit is 10 (-6) years.
⑩ temperature range: refers to the working state of the ambient temperature allows changes in the range.