The invention discloses a successive approximation type analog-to-
digital converter weight calibration method. The weight calibration method comprises the following steps that: in a
capacitor array including n capacitors having capacitances disposed from a high bit to a low bit: Cn-1, Cn-2, and the like, C0; the weight of the ith
capacitor is represented by BWi and conforms to the condition: as shown in the specification; the weight of the ith
capacitor Ci is obtained by gradual calibration of the weights of the capacitors Ci-1, Ci-2, and the like, C0; a calculation method is as follows: as shown in the specification; b0, b1, and the like, bi-1 are digital codes obtained during calibration of Ci and corresponding to the capacitors C0, C1, and the like, Ci-1; BW0 is a preset value, whereini, j belongs to {0, and the like, n}, and n is a positive integer; after the weight calibration is completed, the successive approximation type analog-to-
digital converter obtains non-binary redundancy digital codes bn-1, bn-2, and the like, b0 for an analog input; and a binary
quantitative result is obtained according to a formula as shown in the specification. According to the successive approximation type analog-to-
digital converter weight calibration method, by use of the redundancy characteristic of a non-binary SARADC (Successive Approximation type Analog-to-
Digital Converter), a high bit weight to be calibrated is less than a sum of low bit weights, and is calibrated by using an existing structure of the SARADC and a conversion mechanism; the high bit is calibrated by the low bit; under the condition that the area and the complexity of a circuit are not increased as far as possible, a bit weight of a capacitor is precisely calibrated, and high-precision analog-digital conversionis realized.