Research And Design Of High Precision Analog Multiplier

With the improvement and promotion of 5G,artificial intelligence and other technologies,analog multipliers have become the second largest general-purpose analog chip after the operational amplifiers.The accuracy of analog multipliers would directly affect the performance of various systems.The research of high-precision analog multipliers has always been one of the research hotspots in the field of analog integrated circuits.In this paper,a high-precision analog multiplier is designed based on bipolar integrated circuit process with the completion of the circuit design and simulation optimization,layout design and verification.The main work completed and the results obtained are as follows:(1)The classic double-balanced Gilbert multiplier unit is used as the core of the circuit,and the linearization compensation circuit was added to preprocess the input signal of the Gilbert unit,so that when the input signal at the X terminal is the voltage range from-9V to9V the output is changed from-40mV to 40mV and the Gilbert unit is compensated.The simulation results verify that the linearization circuit can completely solve the problems of the non-linearity of the Gilbert unit and the narrow input range.(2)The bias circuit uses V_BEand PTAT circuits to compensate each other to achieve a stable current.Its working voltage range can reach 7V to 15V,and the temperature drift is3.1?A from-45?to 85?,which can meet the parameters of this article;(3)Through a high-performance operational amplifier,the Gilbert unit dual-port to single-ended output is realized and the load capacity of the system is improved.The classic Miller compensation method is adopted to increase the stability of the system;(4)A high-precision analog multiplier is designed and verified with an accuracy of0.08%,an output offset voltage of-557nV,and a-3d B bandwidth at both ends of up to13.16MHz and 14.99MHz,reaching the expected indicators;(5)The chip layout is designed based on the selected bipolar integrated circuit process rules,the layout area is 3.3mm×1.7mm,and it has passed DRC and LVS simulation verification.The influence of process deviation is evaluated in detail,and a reasonable modification plan is designed.