The Test System Design Of Fast Charging Chip Based On ATE And The Research Of Trim Technology In The Test

With the rapid development of semiconductor technology,the integration of chips is getting higher and higher.In order to ensure the normal operation of these highly integrated chips,it is very important to accurately test them.At the same time,due to the influence of the manufacturing process,the outputs of the bandgap reference source and the oscillator will have a certain degree of deviations,and these deviations will affect the performance of the chip.The trim techniques modify these parameters to improve the accuracy of the chip during the phase of ATE testing.Firstly,a test system is designed based on ASL1000 for a quickcharge chip iW627 produced Dialog company in the dissertation.The test system can test DC parameters,including continuity,leakage and impedance,and functional parameters,including power-on reset,over-voltage protection and under-voltage lock.Secondly,in order to reduce variations of manufacturing process,the trimming circuits of bandgap reference voltage source and oscillator are designed,and then the corresponding trim test circuits are designed to trim voltage of the bandgap reference and frequency of the oscillator.The test results show that the trimming circuits can control the output variations of bandgap reference voltage source and oscillator within±0.03V and ±6KHz respectively,and make the output precision of bandgap reference voltage source and oscillator reach 99.37%and 94%respectively.Meanwhile,to reduce the test time in trim process of bandgap reference voltage source and oscillator,the test algorithms of trim circuits pre-trimming process is optimized.The algorithms can effectively reduce the average trim test time of bandgap reference voltage source and oscillator to 558.16ms and 57.44ms separately,and shorten the trim test time to 22.1%and 33.5%separately.The accuracy of algorithms is verified by testing a large number of chips.Finally,based on the test system and the trimming test circuits of bandgap reference voltage source and oscillator,the chips are tested and the test datas are obtained.Condisering the mass production of chips,some test parameters of the chip are analyzed by histogram,Gauss distribution,Six Sigma quality standard,Cp,Cpk and GR&R to ensure the reliability of the chip testing.