Calculate INL and DNL of DAC

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Load the digital input and the analog output of a DAC from MAT files.

load 'digital.mat'
load 'analog.mat'

The nominal analog dynamic range of the DAC is [-1,1]. Turn on plotting for the output converter threshold. Calculate INL and DNL using both best fit and endpoint methods.

inldnl(a,d,[-1 1],'DAC','GenPlotData','on','INLMethod','All','DNLMethod','All')
INLDNL discarded 759 intervals that contained 5062 data points in total.
This made the analog value sets associated with codes [-16, -16, -16, -16, -16, -16, -15, -15, -15, -15, -15, -15, -15, -15, -15, -15, -15, -15, -15, -15, -15, -15, -15, -15, -15, -14, -14, -14, -14, -14, -14, -14, -14, -14, -14, -14, -14, -14, -14, -13, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15] contiguous.

Figure contains 2 axes objects. Axes object 1 with title Integral Nonlinearity (INL), ylabel INL, LSB contains 2 objects of type line. These objects represent Endpoint, Best Fit. Axes object 2 with title Differential Nonlinearity (DNL), xlabel Digital Code Value, ylabel DNL, LSB contains 2 objects of type line. These objects represent Endpoint, Best Fit.

ans = struct with fields:
                Type: 'DAC'
               NBits: 5
                 LSB: 0.0625
        MissingCodes: [0×1 double]
               Codes: [-16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15]
    IdealCodeCenters: [-1 -0.9375 -0.8750 -0.8125 -0.7500 -0.6875 -0.6250 -0.5625 -0.5000 -0.4375 -0.3750 -0.3125 -0.2500 -0.1875 -0.1250 -0.0625 0 0.0625 0.1250 0.1875 0.2500 0.3125 0.3750 0.4375 0.5000 0.5625 0.6250 0.6875 0.7500 0.8125 0.8750 0.9375]
         CodeCenters: [-0.9522 -0.8820 -0.7987 -0.7288 -0.6557 -0.5862 -0.5165 -0.4488 -0.3785 -0.3122 -0.2421 -0.1673 -0.1028 -0.0401 0.0256 0.1009 0.1657 0.2299 0.2963 0.3627 0.4323 0.4956 0.5580 0.6195 0.6536 0.7638 0.8304 0.8970 … ] (1×32 double)
       CodeCenterStD: [0.0246 0.0261 0.0287 0.0280 0.0254 0.0237 0.0207 0.0212 0.0175 0.0177 0.0228 0.0143 0.0106 0.0147 0.0153 0.0228 0.0079 0.0189 0.0107 0.0178 0.0144 0.0109 0.0126 0.0168 0.0116 5.7752e-06 1.1871e-05 9.4212e-06 … ] (1×32 double)
         EndpointINL: [1.7764e-15 0.0661 0.3424 0.4027 0.5151 0.5695 0.6270 0.6522 0.7200 0.7221 0.7866 0.9252 0.8999 0.8462 0.8394 0.9862 0.9666 0.9355 0.9402 0.9447 1.0017 0.9572 0.8977 0.8240 0.3113 1.0180 1.0258 1.0338 -1.0900 -1.0818 -0.0076 0]
          BestFitINL: [-0.6218 -0.5555 -0.2791 -0.2186 -0.1061 -0.0516 0.0061 0.0314 0.0994 0.1016 0.1663 0.3050 0.2799 0.2263 0.2196 0.3665 0.3471 0.3161 0.3210 0.3256 0.3827 0.3384 0.2790 0.2055 -0.3071 0.3997 0.4077 0.4159 -1.7078 … ] (1×32 double)
         EndpointDNL: [0.0661 0.2763 0.0604 0.1124 0.0544 0.0575 0.0252 0.0678 0.0021 0.0645 0.1386 -0.0253 -0.0537 -0.0068 0.1468 -0.0196 -0.0311 0.0047 0.0045 0.0570 -0.0444 -0.0596 -0.0736 -0.5127 0.7067 0.0079 0.0080 -2.1238 0.0082 1.0742 0.0076 0]
          BestFitDNL: [0.0663 0.2764 0.0605 0.1125 0.0545 0.0577 0.0253 0.0680 0.0022 0.0647 0.1387 -0.0251 -0.0536 -0.0067 0.1470 -0.0195 -0.0310 0.0049 0.0047 0.0571 -0.0443 -0.0594 -0.0735 -0.5126 0.7068 0.0080 0.0081 -2.1236 0.0083 1.0743 0.0077 0]
         BestFitPoly: [0.0661 0.1440]
         OffsetError: 0.7641
     OffsetErrorUnit: 'LSB'
           GainError: 1.7843
       GainErrorUnit: 'LSB'
                 TCR: [1×32 struct]