Research And Implementation Of DDR4 High Speed Memory Test Method

Semiconductor memory occupies half of the semiconductor industry market,with DRAM and NAND Flash market accounting for more than 95%.The single particle capacity of DDR4 high-speed memory is increased to 16Gb,and the data transmission rate is increased to 3200Mbps.The larger capacity and higher data transmission rate pose a huge challenge to chip testing and accelerate the research on DDR4 high-speed memory testing methods.This subject researches the DDR4 high-speed memory test method,which can realize the function test,DC parameter and AC parameter test at the highest data rate of3200Mbps.The function test,current test,and Speed Grade test procedures are designed in detail,and the overall the program includes the design of software and hardware and the research of test methods.The main research contents include:(1)Overall scheme design.According to the DDR4 test requirements,the DDR4 test requirements were put forward.Through the comparison of the three memory test systems,the ATE-based memory test system was finally selected and the test plan was developed,which mainly includes the test system index analysis,DIB board design requirements,and DDR4 memory circuit test Sequence,test system procedures,basic test methods and memory test programming environment,and finally completed the overall plan design,laying the foundation for the next test(2)Research on hardware design and testing methods.Design the DIB board according to the requirements of high-speed board manufacturing and the test system.Through the analysis of the main fault models of the memory,the test algorithms that can detect the corresponding fault models are studied,mainly including the N-type test algorithm,the N² type test algorithm and the N^3/2 type test algorithm.This algorithm compares the pros and cons of the test algorithm in terms of test time,complexity,and fault coverage,and concludes that the N-type test algorithm can detect the proposed fault.(3)Test program development.Use ATE to simulate the DDR4 controller,design the test patterns required by the test algorithm in the functional test,the test patterns in the current test,and the Speed Grade test program in detail,develop the test process,and verify the chip test results.This article designs a set of DDR4 high-speed memory test schemes based on ATE,selects Advantest V93000 STH integrated circuit test system,uses DDR4 SDRAM chip MT40A1G8 for testing,verifies the function test and index accuracy at a data rate of3200Mbps,and obtains the test results.Established a DDR4 memory test technology platform.