High precision on-chip clock oscillator based on cmos technology

Abstract

The invention discloses a complementary metal oxide semiconductor (CMOS)-process-based high-accuracy on-chip clock oscillator, which comprises a frequency voltage conversion circuit, an integral circuit, a voltage-controlled oscillator, an automatic current trimming circuit, an adjustable temperature coefficient current source and a band gap reference circuit, wherein the frequency voltage conversion circuit, the integral circuit and the voltage-controlled oscillator are sequentially connected into a closed loop structure. The frequency voltage conversion circuit, the integral circuit and the voltage-controlled oscillator form a closed loop control oscillator circuit, so that the output frequency of the oscillator circuit is controlled by the whole closed loop without the influence of process variations of MOS transistors. Due to the adoption of the closed loop, the oscillator circuit has high noise performance. In addition, a temperature compensation current source and the automatic current trimming circuit are adopted for the whole loop, so that the oscillator circuit is ensured to have high temperature and process stability. Moreover, the oscillator circuit is simple and high in clock accuracy, and an external quartz crystal oscillator of an electronic system can be replaced.

Description

technical field [0001] The invention relates to the field of electricity, in particular to a clock oscillation circuit, in particular to a high-precision on-chip clock oscillator based on CMOS technology. Background technique [0002] In various electronic systems, a crystal oscillator (XTAL) is an essential clock reference signal. Widely used in computers, remote controls and automatic control circuits. It is mainly used in frequency generators in communication systems to generate clock signals for data processing equipment to maintain the synchronization of signal transmission. Although crystal oscillators can generate accurate clock signals, the clock signals generated by crystal oscillators have the disadvantages of high cost, high power consumption of the system, and the shortcomings of not being able to be integrated into the chip. There is no way to achieve low-cost, Requirements for low power consumption and miniaturization, especially in biomedical chips and IoT c...

AI Technical Summary

Problems solved by technology

For example, on-chip micro-electromechanical systems (MEMS) are used to realize on-chip crystal oscillators, but MEMS has the disadvantages of high power consumption, high cost, and inability to implement standard CMOS technology, which limits its application and development.

Although some oscillator structures abroad can achieve good frequency stability, they require external passive components, and the temperature and voltage coefficients of frequency are not very good.

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