A Configurable Voltage Controlled Oscillator for FPGA

Abstract

Provided is a configurable voltage-controlled oscillator applied to an FPGA. A ring oscillator serves as a core part of the voltage-controlled oscillator and is provided with extra digital control signals used for controlling frequency of an oscillation center. The control signals are configured by means of configuration information of the FPGA, center frequency of the voltage-controlled oscillator can be adjusted, and therefore output frequency of the voltage-controlled oscillator can be continuously adjusted within a large range.

Description

technical field [0001] The invention relates to a voltage-controlled oscillator, in particular to a configurable voltage-controlled oscillator with a wide frequency range applied in FPGA. Background technique [0002] A voltage-controlled oscillator (hereinafter referred to as VCO) is essentially an oscillator. The oscillation frequency is controlled by a control voltage and can be adjusted within a certain range, which is the difference between a VCO and an ordinary oscillator. This feature makes the VCO widely used in phase-locked loops (hereinafter referred to as PLLs). [0003] figure 1 It is a schematic diagram of a typical PLL structure. Its working principle is as follows: the phase frequency detector compares the frequency and phase relationship between the reference clock and the feedback clock, the charge pump and the low-pass filter adjust the control voltage, adjust the oscillation frequency of the VCO, and ensure that the output clock is consistent with the ref...

AI Technical Summary

Problems solved by technology

However, the traditional VCO can only be adjusted around a specific frequency, which limits the application range and occasions of the PLL.

Images