| As society relies more and more on smart products,its functional requirements for products are also getting higher and higher.As one of the important components of the product equipment,the chip is currently facing two major challenges.The process technology cannot continue to advance and the chip cannot meet the requirements of high performance and low power consumption.The voltage reference source,as the basic module in the design of the analog integrated circuit in the chip,complements each circuit module and even the overall performance of the circuit,and occupies an important position in the circuit.Therefore,designing a high-performance and low-power voltage reference circuit structure is particularly important for future development.In this paper,two reference source circuits are designed,which are only CMOS reference and hybrid reference source.Among them,the core part of the circuit is designed from the application of different devices,and the basic performance of the circuit and the subsequent improvement direction are obtained through simulation calculation.Before the design of the reference voltage,the MOS tube and the BJT tube were theoretically explained,including the basic concept of the device,the working principle and the temperature characteristics of the device,and the circuit structure proposed in recent years was technically summarized and analyzed.Through the formula derivation and performance analysis of the three circuit structures of traditional bandgap reference,only CMOS reference voltage and hybrid voltage reference,the following conclusions are drawn: the traditional bandgap reference voltage source has a better compatible process and can achieve very good results.Good accuracy,but the power supply voltage and bias current are limited,which is not conducive to low-power applications;the only CMOS voltage reference circuit has the characteristics of low power consumption,but its parameter threshold voltage is not easy to control due to process changes;hybrid type has accuracy Advanced features,but the power consumption has not yet reached a lower level.By summarizing the shortcomings of existing circuits,two voltage reference source circuits are proposed.The first circuit structure is a only CMOS voltage reference.First,the working principle is derived from the formula,and the linear adjustment rate of the circuit is analyzed.Then use simulation software to perform parameter scan simulation on the circuit and extract data calculations,and obtain a reference voltage of 247 m V.In the best case,the temperature coefficient is 17.9ppm/℃.However,the only CMOS circuit structure still has defects,that is,the linear adjustment rate is high and the power consumption cannot be reduced to a low level,so some parameters are optimized,and a second circuit structure,a hybrid voltage reference source,is designed.This circuit structure achieves a temperature coefficient of 52.9ppm/°C in the best case,a linear adjustment rate of 1.3%/V,a power consumption of only 6.8n W and a power supply rejection ratio of-40.6d B at a frequency of 100 Hz to 417.9m V.The reference voltage.This structure realizes the improvement of some parameters of the only CMOS circuit structure,and the linear adjustment rate is increased by 11 times.Although this circuit structure sacrifices part of the temperature coefficient,the power consumption performance is reduced by 1048 times. |
