Design Of High Power IGBT Detection And Conversion Circuit Based On Shunt

In recent years,IGBT has been widely used as the core device of power electronics technology in household appliances,frequency converters,and smart grids.Detecting the operating current of the IGBT is an important function in the IPM(Intelligent Power Module).The paper is based on the Highly Integrated IPM Research project of the project team and completes the IGBT current detection and conversion circuit design of the DBC backplane integrated shunt.The overall circuit mainly includes the detection circuit and the conversion circuit part.The detection circuit uses a current-mode feedback instrumentation amplifier with a multi-path chopping offset stabilization structure consisting of a high-frequency path and a low-frequency path:including a multipath compensation opamp,a chopper modulation circuit,a ripple cancellation circuit,and a gainboot circuit and floating A and B common source output circuit design.The conversion circuit is mainly to convert the detection circuit to digital code through the ADC,including the pre-latch comparator,segmented charge redistribution DAC with sample and hold function,sampling bootstrapping Design of switches,fourteen-bit counters,and successive approximation registers.Based on the CSMC 0.25um BCD process,Spectre was used to simulate the circuit.The PSS(periodic stability analysis)is used to simulate the offset voltage and equivalent input noise of the detection circuit under different corners.The results show that the equivalent input offset voltage is between 10 and 30uV and the equivalent input noise is 100nV/(?)Hz.Satisfy the precision design requirements of the detection circuit.Through the simulation of the conversion circuit,the results show that:when the input voltage is 2V,the SAR ADC can correctly complete the successive approximation process and simulate the dynamic parameters under different corners.The circuit proposed in this paper is compared with other literatures.The results show that the detection circuit in this paper has certain advantages in offset voltage and equivalent input noise.Finally,the simulation result of the whole circuit shows that the circuit can detect the small signal and the conversion process can be completed correctly through the conversion circuit.