Chip voltage trimming method

Abstract

The invention discloses a chip voltage trimming method, which comprises the following steps of: when an initial value of a to-be-trimmed voltage is between a first threshold value and a second threshold value, determining assignment values of all trimming positions, or when the initial value is smaller than the first threshold value or larger than the second threshold value, determining the assignment value of the highest trimming position based on a voltage range in which the initial value is located; executing an iteration step until the pre-trimming value is greater than or equal to a first threshold value and less than or equal to a second threshold value, and ending the execution of the iteration step so as to sequentially determine the assignments of all trimming positions after the highest trimming position; and carrying out a test to obtain a final value of the voltage to be trimmed. The iteration step further comprises: carrying out pre-assignment on a next trimming position, writing a determined trimming position assignment and a pre-assignment into a chip, and carrying out the test to obtain a pre-trimming value of the voltage to be trimmed; and judging the voltage range of the pre-trimming value, and further determining the assignment of the current trimming position of the chip. According to the invention, the trimming precision can still meet the requirements during mass production operation, and the product yield is improved.

Description

technical field [0001] The invention relates to the technical field of integrated circuit testing, in particular to a chip voltage trimming method. Background technique [0002] In the field of integrated circuits, due to the influence of the distribution of the process itself, the parameters of the produced chips will have certain deviations. In applications that require parameter accuracy, it is necessary to use trimming methods to reduce the influence of parameter distribution and improve parameter accuracy. consistency to meet application requirements. [0003] Currently known trimming methods mainly include electrical trimming, laser trimming, eFuse or EEROM code writing trimming. The trimming code trims the fuse. [0004] Such as figure 1 as shown, figure 1 Show the schematic flow chart according to the trimming method of existing chip voltage, first test and obtain the initial value of the chip voltage to be trimmed (step S01); then bring the initial value into th...

AI Technical Summary

Problems solved by technology

During batch testing of chips, the trimming weight of the chip will change with the change of mass production batches, which will cause the value of the trimming weight LSB corresponding to the lowest effective trimming bit to vary during each trimming. If the look-up table formula calculation method is still used at this time, the trimming accuracy will not meet expectations (plus or minus half LSB), and even lead to a low product yield rate of the chip

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