Low Temperature Drift Analysis And Design Of Ring Oscillator

The oscillator is an important part of many electronic systems. Its applications range from the microprocessor clock generation to carrier synthesis in cellular telephones, structure parameters and performance requirements of the difference is very big. Along with CMOS technology development,the structure of the oscillator is changing. This not only provides the option for the circuit designer,but also meets the application of oscillator in different situations. The feature of ring oscillator is more conductive to high-frequency characteristics, wide adjustment range, highly linear oscillator.However, temperature has a great influence on the frequency stability of the oscillator,so it is necessary to compensate the temperature of the ring oscillator.Aiming at the design of low temperature drift of ring oscillator, this paper puts forward the structure of current control, at first,this paper introduces the research background and research situation of the oscillator; and then introduces the basic structure and working principle of the ring oscillator; then according to the design scheme, this paper designs every module circuit and the whole circuit; finally, this paper finishes the design of the layout.The ring oscillator circuit is designed and validated according to CSMC 0.5um CMOS technology library, through the simulation to achieve the design of low temperature drift of ring oscillator. The test result shows that the frequency is about 1.2MHz and the error(△f/f) is about7.4‰ in the temperature range 0℃-100℃.The design of the ring oscillator is especially suitable for application in DC-DC converter.