Silicon-based ring oscillator circuit with stable frequency

Abstract

The invention provides a silicon-based ring oscillator circuit with stable frequency, which comprises at least one phase inverter, the number of the phase inverters is an odd number, the phase inverters are connected in series in a circuit, resistors are connected in series between the phase inverters, capacitors are connected in parallel between the phase inverters and the resistors. The resistance and the capacitance are small relative to transistors along with process changes, and change towards opposite directions under the process and temperature changes, so that the RC time constant change is small, and the output frequency of a oscillator is stable. In a silicon-based integrated circuit, the resistors are connected in series and the capacitors are connected in parallel behind the phase inverters to form an annular oscillator, so that the stability of the output frequency can be realized. The area is small, and changes along with process and temperature are small. The changes of the resistors and the MOS capacitors are smaller relative to the transistors along with the process change and are towards the opposite direction under the process and temperature change, so that the RC time constant change is small, and the output frequency of the oscillator is stable.

Description

technical field [0001] The invention relates to the technical field of ring oscillators, in particular to a silicon-based ring oscillator circuit with stable frequency. Background technique [0002] Oscillator is a circuit that converts DC power into AC power of a certain frequency. Its application ranges from clock generation of microprocessors to carrier synthesis in cellular phones to the realization of switching power supplies. The required structure and performance parameters are very different. Big. Designing stable, high-performance oscillators using silicon-based processes continues to pose challenges. [0003] In integrated circuit design, the structure of the oscillator mainly includes voltage-controlled oscillator (VCO), LC oscillator, ring oscillator and so on. Although the existing ring oscillator composed of an odd number of inverters has the advantages of simple structure, reliable function, and low implementation cost, the output frequency is greatly affect...

AI Technical Summary

Problems solved by technology

Although the existing ring oscillator composed of an odd number of inverters has the advantages of simple structure, reliable function, and low implementation cost, the output frequency is greatly affected by the process deviation and temperature in the integrated circuit manufacturing process, and the output frequency can vary up to More than three times, it is no longer suitable for the development of electronic systems with higher and higher requirements, such as 5G, etc.

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