A charge-pump phase-locked loop using dual voltage-controlled voltage-controlled oscillators

Abstract

The present invention provides a charge pump phase-locked loop adopting a dual-circuit voltage control voltage-controlled oscillator, the phase-locked loop includes an N-stage ring oscillator B200 and an amplification and shaping circuit B201, receiving the charge pump and The loop filter generates two control voltages respectively, and generates a sine wave oscillation signal of a certain frequency according to the control voltage, and shapes it into a square wave, which is used as the input signal of the digital frequency divider of the charge pump phase-locked loop. Compared with the traditional voltage-controlled oscillator, the present invention uses two control voltages VC1 and VC2 as the tuning voltage, VC1 as the coarse tuning voltage, and VC2 as the fine tuning voltage, taking into account the tuning speed and the quality of the oscillation signal, and can effectively accelerate the charge pump lock Locking of the phase ring.

Description

Technical field [0001] The present invention relates to a charge pump lock phase loop using a dual voltage controlled voltage controlled oscillator, belonging to the technical field of integrated circuits. Background technique [0002] The phase-locked loop is a frequency and phase synchronization technique implemented by the feedback control principle, which provides a low noise clock signal that has been widely used in the fields of wireless communication, navigation, and computers. The charge pump locking ring is a typical representative of digital-to-mode mixed lock, which is zero, with high speed, low jitter, low power consumption and other significant advantages, and is currently the most widely used phase locked loop. The basic structure of the charge pump lock ring figure 1 Indicated. [0003] As the integrated circuit process continues to improve and the continued increase in scale, the requirements of the integrated circuit system on the performance of the phase-locked ...

AI Technical Summary

Problems solved by technology

[0004] At present, most common charge pump phase-locked loops use a voltage-controlled oscillator structure with a single control voltage. The locking speed of the phase-locked loop is improved through bandwidth switching or pre-start strategies. The main problem is that additional circuit modules need to be designed, which increases hardware consumption. and layout area, while bringing about an increase in power consumption, which is not conducive to integration

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