Quick oscillation starting circuit and method, crystal oscillator and integrated chip

Abstract

The invention relates to a fast oscillation starting circuit and method, a crystal oscillator and an integrated circuit. The quick oscillation starting circuit injects a first current signal consistent with the output clock frequency of a crystal oscillation module into the crystal oscillation module and comprises a driving circuit body, a frequency-locked loop circuit and a switching circuit, theinput end of the driving circuit body is connected with a crystal oscillation module, and the output end of the driving circuit body is connected with the frequency-locked loop circuit and used for receiving an output clock of the crystal oscillation module, amplifying the output clock and then inputting the amplified clock to the frequency-locked loop circuit for driving; the input end of the frequency-locked loop circuit is connected with the driving circuit, the output end of the frequency-locked loop circuit is connected with the crystal oscillation module through the switching circuit, and the frequency-locked loop circuit is used for receiving the amplified output clock, locking the output frequency as the frequency of the output clock and injecting a first current signal into the crystal oscillation module; the switch circuit is located between the frequency-locked loop circuit and the crystal oscillation module and is used for entering a disconnection state to disconnect the frequency-locked loop circuit and the crystal oscillator module after the crystal oscillation module completes oscillation starting. Injection locking is carried out from the outside, and oscillation starting of a crystal oscillator can be rapidly accelerated.

Description

technical field [0001] The invention relates to the technical field of circuits, in particular to a fast start-up circuit, a method, a crystal oscillator and an integrated chip. Background technique [0002] Quartz crystal oscillator is a resonant device made by using the piezoelectric effect of quartz crystal. Because quartz crystal has a very high quality factor, quartz crystal oscillator can generate accurate and stable oscillation waveforms, and is widely used for vibration In fields such as clocks and watches, military industry, and communications that require high frequency, most of the integrated chip systems currently use crystal oscillators to provide clock signals for the system. However, in the field of electronics, at present, the design demand for integrated circuits with low power consumption and low cost is increasingly prominent. Among the many design indicators of the crystal oscillator circuit, the start-up time is particularly important, especially for so...

AI Technical Summary

Problems solved by technology

However, from the improvement of the parameters of the crystal oscillator itself, it is easy to change due to changes in temperature, process, and voltage, and the acceleration time is also uncertain, which leads to poor product consistency and will be affected by the process.

Moreover, from the improvement of the parameters of the crystal oscillator itself, the reduction time is relatively limited. Generally speaking, it is difficult to reduce it to below 400uS

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