Patent ID: 8502723

Claim:
A method for evaluating weighting of elements of a digital-to-analog converter (DAC), the DAC comprising N composed elements represented by E 0 , E 1 , . . . , E N-1 , the method comprising: providing a reference element E ref coupled to the DAC; during a first phase of an 0 th period, inputting a first value V 1 for the composed element E 0 and inputting a second value V 0 for the other composed elements E 1 , . . . , E N-1 , so an equivalent open circuit output is V MCW0 ; during a second phase of the 0 th period, inputting the second value V 0 for all of the composed elements E 0 , E 1 , . . . , E N-1 , and adjusting the input value of the reference element E ref , so the equivalent open circuit output V dig0 is approximately equal to V MCW0 , and according to the input value of the reference element E ref , obtaining a rational multiple K ref,0 less than 1, wherein a weighting value of the composed element E 0 is evaluated according to the rational multiple K ref,0 ; during the first phase of an i th period, inputting the first value V 1 for the composed element E i , and inputting the second value V 0 for the other composed elements E 0 , . . . , E i−1 , E i+1 , . . . , E N-1 , so the equivalent open circuit output is V MCWi ; and during the second phase of the i th period, inputting the second value V 0 for the composed elements E i , E i+1 , . . . , E N-1 labeled greater than or equal to i, adjusting the input value of the reference element E ref , and selecting one of the first value V 1 and the second value V 0 as the input values of the composed elements E 0 , E 1 , . . . , E i−1 , so the equivalent open circuit output V digi is approximately equal to V MCWi , and according to the input value of the reference element E ref and the input values of the composed elements E 0 , E 1 , . . . , E i−1 , obtaining the coefficients K 0,i , K 1,i , . . . , K i−1,i and a rational multiple K ref,i less than 1, wherein a weighting value of the composed element E i is evaluated according to the coefficients K 0,i , K 1,i , . . . , K i−1,i and the rational multiple K ref,i , N is a positive integer greater than 1, and i is a positive integer greater or equal to 0 and less than N.