Voltage controlled oscillator

Abstract

The invention discloses a voltage controlled oscillator capable of realizing oscillation during the whole range of voltage control from zero to power voltage. The voltage controlled oscillator comprises a main biasing circuit, a secondary biasing circuit, a ring oscillator, an oscillator generating circuit of a main power supply regulating circuit and a secondary power supply regulating circuit; the secondary biasing circuit outputs secondary biasing voltage to the secondary power supply regulating circuit under the function of voltage control, the secondary power supply regulating circuit is turned on and controls the ring oscillator to generate oscillation signals; the main biasing circuit outputs main biasing voltage to the main power supply regulating circuit under the situation that the control voltage is less than voltage threshold and the main power supply regulating circuit is turned off; the main biasing circuit outputs main biasing voltage to the main power supply regulating circuit when the control voltage is more than or equal to the voltage threshold, the main power supply regulating circuit is turned on and controls the ring oscillator to generate oscillation signals. The oscillator is capable of realizing oscillation during the whole range of voltage control from zero to power voltage and is characterized by high degree of linearity and broadband.

Description

technical field [0001] The invention relates to a voltage-controlled oscillator, in particular to a voltage-controlled oscillator with two power supply regulating circuits. Background technique [0002] The frequency generation source is an essential part of most electronic systems, and it is the core of wireless communication systems and clock generation circuits. The voltage-controlled oscillator is an oscillator whose oscillation frequency changes with the change of the external control voltage, and is a key component of the frequency generation source. In many modern communication systems, voltage-controlled oscillators are frequency-tunable signal sources used to enable fast frequency tuning of phase-locked loops and other frequency synthesis source circuits. The development of electronic devices and electronic systems continuously promotes the update and progress of voltage-controlled oscillator technology. From the perspective of modern and future wireless systems, e...

AI Technical Summary

Problems solved by technology

Although compared with earlier current-mode voltage-controlled oscillators, figure 1 The structure of the shown current-mode voltage-controlled oscillator has been greatly simplified, and the output oscillation swing has also been improved, but the linearity of the bias circuit structure of the circuit is not ideal at low power supply voltages, and the voltage-controlled oscillator is still Oscillation starts only when the external input control voltage is greater than the threshold voltage of NMOS transistor M1, and the effective voltage adjustment range is narrow

Images