【作者】 孙光明；

【导师】 鲁征浩；

【作者基本信息】 苏州大学 ， 集成电路工程（专业学位）， 2023， 硕士

【摘要】 随着芯片设计与制作技术的发展,集成电路设计经历了从晶体管到逻辑门最终到IP(知识产权模块)的集成发展,即SOC(片上系统)设计技术。其中时钟产生电路是整个SOC时钟电路中重要的组成部分。在常用的时钟电路中,RC振荡电路因其面积小、成本低、易集成等优点被广泛应用。本文通过对开环和闭环振荡器结构进行分析,设计出两种不同类型的低温漂高精度振荡器电路。本文利用两种不同的电路结构,设计出两种不同频率的振荡器,输出频率分别为2.54MHz和16MHz。主要工作包含:(1)分析温度、电源电压和比较器翻转延迟对振荡器输出频率精度的影响;(2)从温度、电源电压分析结果出发,设计低温漂基准电流电压源电路、LDO(低压差线性稳压器)电路提升整体振荡电路输出频率的精度和稳定性;(3)随着高频电路的应用,比较器翻转延迟占据振荡周期比值越来越大,对比分析多种线性补偿技术,设计出一种含有检测补偿功能的电路结构增加振荡电路的线性度;(4)从芯片实际应用出发,增加过温保护电路,确保芯片在有效温度范围工作,提升芯片的使用寿命。本文设计电路主要采用CMOS0.18um工艺,对电路进行了前仿真验证、版图设计和后仿真验证。根据后仿真结果可以得出结论:温度范围在-40℃到125℃变化时,振荡器的振荡频率变化分别为0.2%和0.3%;电源电压范围在1.7V～1.9V和3.0V～3.6V变化时,振荡器的振荡频率变化分别为0.15%和0.02%。增加的频率修调电路能够补偿由于工艺制备导致振荡器输出频率精度偏差,在工作电源电压1.8V,TT工艺角的条件下,过温保护电路在158℃左右关闭电流镜使振荡电路停止工作。更多还原

【Abstract】 With the development of chip design and production technology,integrated circuit design has developed from transistor integration to logic gate integration,and now to IP(Intellectual Property)integration,namely SOC(System on chip)design technology.The clock generating circuit is an important part of the whole SOC clock circuit.RC oscillator circuit is widely used in common clock circuits because of its advantages of small area,low cost and easy integration.In this paper,two different types of low temperature bleach high precision oscillator circuits are designed by analyzing the structure of open loop and closed loop oscillators.In this paper,two kinds of oscillators with different frequencies are designed by using two different circuit structures.The output frequencies are 2.54MHz and 16MHz respectively.The main tasks include:(1)analyzing the influence of temperature,power supply voltage and comparator rollover delay on the accuracy of oscillator output frequency;(2)Based on the analysis results of temperature and power supply voltage,the low-temperature drift reference current voltage source circuit and LDO(Low Dropout Regulator)circuit are designed to improve the accuracy and stability of the output frequency of the overall oscillation circuit;(3)With the application of high-frequency circuit,the ratio of oscillation period occupied by the comparator turn-over delay is increasing.Multiple linear compensation technologies are compared and analyzed,and a circuit structure containing a detection compensation function is designed to increase the linearity of the oscillation circuit.(4)From the practical application of the chip,the overtemperature protection circuit is added to ensure that the chip works in the effective temperature range and improves the service life of the chip.The circuit designed in this paper is based on CMOS 0.18um process,and the pre-simulation verification,layout design and post-simulation verification of the circuit are completed.The simulation results show that when the temperature ranges from-40℃ to 125℃,the oscillator frequency changes by 0.2%and 0.3%,respectively.When the supply voltage ranges from 1.7V to 1.9V and from 3.0V to 3.6V,the oscillator oscillates at 0.15%and 0.02%,respectively.The added frequency adjustment circuit can compensate for the deviation of oscillator output frequency precision caused by the process preparation.Under the condition of working power supply voltage 1.8V and TT process Angle,the over temperature protection circuit closes the current mirror at about 158℃ to stop the oscillation circuit.更多还原