Design Of High-performance Hall Current Sensor Chip

With the development of sensor technology,Hall current sensors have been widely used in the fields of industrial automation,automotive electronics,aerospace and defense.However,the performance of Hall current sensor is seriously affected by the problems of flicker noise,offset voltage and Hall element sensitivity changing with temperature.Therefore,the research of offset voltage and noise suppression method and sensitivity temperature compensation method,and the design of a Hall current sensor chip with low noise,low offset voltage and good sensitivity temperature characteristics has important theoretical significance and engineering application value.By analyzing the source of the offset voltage of the Hall element,the quadrature current method is used to separate the Hall voltage and the offset voltage,and the design idea of sample-hold-average-offset is adopted to the separated offset voltage for the subsequent circuit eliminate.By analyzing the sources of noise and offset voltage in the signal processing circuit,comparing the advantages and disadvantages of commonly used noise and offset voltage elimination technologies,an offset voltage and noise elimination scheme based on chopper stabilization technology is determined.On the basis of researching traditional chopper technology circuits,Modulation circuit,operational amplifier circuit and filter circuit are improved and designed.By studying the commonly used sensitivity temperature compensation technology,the resistance of the Hall element with the same shape and material is used to offset the effect of the equivalent resistance of the Hall element with the temperature change,so as to realize the sensitivity temperature compensation.At the same time,the key modules such as the bandgap reference circuit,clock signal generating circuit and output stage circuit inside the chip are designed and simulated.Finally,the overall circuit design of the Hall current sensor chip is completed.Based on the SK Hynix 0.18um BCD simulation library file,combined with Hspice software,the overall circuit of the chip was simulated and analyzed,and the results verified the correctness of the circuit function.Finally,based on the SK Hynix 0.18um BCD process model,the overall layout of the chip was designed and drawn,and it passed DRC and LVS verification.The feasibility of the designed layout is verified by the results.