Frequency generating system, voltage controlled oscillator module and method for adjusting signal frequency

Abstract

The invention discloses a voltage-controlled oscillator module which comprises a voltage-controlled oscillator unit and a gain adjustment unit, wherein the voltage-controlled oscillator unit is used for generating a frequency signal according to a control voltage; the gain adjustment unit is electrically connected to the voltage-controlled oscillator unit and used for receiving a first adjustment voltage, a second adjustment voltage and a reference voltage and adjusting the control voltage so as to adjust the frequency value of the frequency signal; the gain adjustment unit comprises an adjustment circuit unit and a reference circuit unit; a first voltage-frequency curve of the frequency value of the frequency signal and the voltage value of the first adjustment voltage is changed in response to a structural characteristic of the adjustment circuit unit. In addition, the invention discloses a signal frequency adjustment method of the voltage-controlled oscillator module and a frequency generation system.

Description

technical field [0001] The present invention relates to a frequency generation circuit and its frequency adjustment method, and in particular to a voltage-controlled oscillator module, its signal frequency adjustment method and frequency generation system. Background technique [0002] Please refer to figure 1 , which shows a schematic circuit diagram of a known voltage controlled oscillator. The voltage-controlled oscillator (VCO) 100 is implemented based on a ring oscillator 110 , which is controlled by a control voltage Vctrl to generate a frequency signal fout. The control voltage Vctrl here is output through the unity gain buffer 120 to drive the ring oscillator 110 . The unit delay elements 112 of each stage of the ring oscillator 110 are inverters implemented by P-type and N-type MOS transistors. Generally speaking, the unit delay elements 112 of each stage of the ring oscillator 110 are very sensitive to the change of the control voltage Vctrl, so as long as the c...

AI Technical Summary

Problems solved by technology

In the known technology, the adjustment method of the gain and bias point of the ring oscillator 110 is achieved by changing the structural characteristics of the unity gain buffer 120, but this method may also cause other problems, including the ring oscillator 110 It is difficult to adjust the gain of the ring oscillator; the gain of the larger ring oscillator 110 will cause larger noise; and the operating range of the control voltage Vctrl is narrow and the operating point is not in the center of the gain curve, etc.

In addition, in some application examples, the operational amplifier used as the unity gain buffer 120 also consumes more power in order to maintain high current, high bandwidth and low noise operation

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