Research On The Analog-digital Mixed Test Channel Of ADC Circuit

With the development of modern integrated circuit technology,chip packaging is highly integrated and high-performance.Analog-to-digital hybrid integrated devices and circuits are rapidly developing towards micro packaging and high integration.The test problem of the analog-digital mixed circuit is to test the analog signal alone and the digital signal separately,and the test complexity is high.The test cost of ATE test is relatively high,and it is difficult to conduct online test and BIST structural test in case of failure in engineering application.Aiming at the difficult problems of online test and BIST structure test,this paper designs a mixed analog-digital test channel of ADC circuit,which combines the analog and digital parts to test,simplify the test complexity and reduce the test cost.Analog-to-digital mixed test channels include MTAP controller,TBIC circuit,ABM circuit and DBM circuit,etc.The modules of the mixed test channel and the 10-bit successive approximation type register were tested and verified by Modelsim simulation.The ADC circuit adopts the successive approximation design with simple structure,small area and low power consumption.Using Cadence ADE software 0.18?m CMOS process library to model the ADC circuit,through Spectre Simulation simulation test analysis,completed the ADC overall circuit test verification.Using Cadence virtuoso to draw the layout,using a capacitive segmented structure of the digital-to-analog converter and a common center compact layout design,reducing the chip layout area.The test results show that the research content of this paper meets the requirements of online testing and BIST structural design,and achieves the research purpose of mixed analog and digital test channels.