Inductance-capacitance voltage-controlled oscillator with adjustable output clock common-mode voltage

Abstract

The invention discloses an inductance-capacitance voltage-controlled oscillator with adjustable output clock common-mode voltage. The inductance-capacitance voltage-controlled oscillator comprises a PowerPad, a band-gap circuit, an LDO circuit, a biasing circuit and an LCVCO circuit. The input end of the PowerPad is connected with an external power supply, and the output end of the PowerPad is connected with the input end of the band-gap circuit, the input end of the LDO circuit and the source electrode of the oscillator current tube. The output end of the band-gap circuit is connected with the input end of the LDO circuit. The output end of the LDO circuit is connected with the input end of the biasing circuit. The input end of the biasing circuit is connected with a first differential signal and a second differential signal, and the output end is connected with the grid of the oscillator current tube. The LCVCO circuit is connected with the drain electrode of the oscillator current tube. The phase noise of the inductance-capacitance voltage-controlled oscillator can be effectively reduced on the premise that the power supply and the power consumption are not obviously increased.Meanwhile, the output clock common-mode voltage of the oscillator is adjusted, and it is guaranteed that the power consumption and the area of the phase-locked loop meet the design requirements.

Description

technical field [0001] The invention relates to the technical field of integrated circuit design, in particular to an inductance-capacitance voltage-controlled oscillator with adjustable output clock common-mode voltage. Background technique [0002] Phase-locked loops (PLLs) are widely used in electronic design. In radio frequency communication systems, phase-locked loops (PLLs) are an extremely critical module and are widely used to provide stable frequencies for transceivers. The RF phase-locked loop circuit is usually composed of a frequency detector, a charge pump, a loop filter, a voltage-controlled oscillator, and a frequency divider. Due to the relatively good phase noise performance, the inductor-capacitor voltage-controlled oscillator (LCVCO) is widely used in RF phase-locked loop (PLL) circuits, and its phase noise and oscillation speed are important performances of a phase-locked loop, especially in high-speed In low-jitter clock applications such as data transm...

AI Technical Summary

Problems solved by technology

Although this structure can effectively reduce the phase noise of the oscillator, it also introduces an inductance module, which requires a considerable increase in area

[0004] As the output clock frequency of the phase-locked loop becomes higher and higher, the swing amplitude will gradually decrease, and the temperature and angle will change. Under the premise of ensuring the stability of the output frequency, how the subsequent circuit can correctly identify the high and low levels of the output clock is also a design. The key point is that in traditional circuits, an additional shaping circuit is usually added to the output of the oscillator to ensure the normal operation of the output clock, which will not only increase the additional area, but also increase the additional power consumption

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