A Ring Voltage Controlled Oscillator Suitable for Low Supply Voltage

Abstract

The present invention discloses a ring voltage-controlled oscillator applicable to a low power supply voltage, including a detection circuit and a main circuit,wherein in the detection circuit, a process variation and a fluctuation of a power supply voltage are converted into a voltage signal through a reference current source and a current mirror, and the voltage signal is converted into a control voltage Vt by an operational amplifier; in the main circuit, the operating frequency of the ring voltage-controlled oscillator is stabilized relative to the process variation and the power supply voltage by the control voltage Vt by changing the load of the ring voltage-controlled oscillator; and a controllable inverter in the main circuit improves the tuning linearity of the ring voltage-controlled oscillator by connecting a PMOS transistor for fixing substrate potential in parallel. The ring voltage-controlled oscillator proposed by the present invention is applicable to design requirements of low voltage and low power consumption, and is stable relative to the process variation.

Description

technical field [0001] The invention relates to a low power supply voltage ring oscillator resistant to process deviation, which belongs to the technology of voltage-controlled oscillators. Background technique [0002] In the radio frequency communication system, the frequency synthesizer is responsible for generating the local oscillator signal, which is the core module in the radio frequency transceiver, and the charge pump phase-locked loop is an extensive and mature structure for realizing the frequency synthesizer. As the main module of the phase-locked loop circuit, the voltage-controlled oscillator occupies a considerable share in the power consumption of the whole system. Therefore, in order to realize the low power consumption of the whole circuit, the low power consumption design of the voltage-controlled oscillator is very important. In addition, the phase noise performance, anti-process deviation performance and anti-power supply voltage fluctuation performance...

AI Technical Summary

Problems solved by technology

However, the main loop and the feedforward loop of the feedforward ring oscillator are both composed of inverters, which are significantly affected by process deviations and power supply voltage fluctuations at low power supply voltages, and the deviation of the oscillation frequency is very large

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