Analog-to-digital conversion calibration method and device

Abstract

The invention provides an analog-to-digital conversion calibration method and device; the method comprises the following steps: allowing an analog-to-digital converter to convert a received tested signal S (n) into a data signal waveform X (n); building a discrete digit signal sequence E (n) according to the data signal waveform X (n); using the discrete digit signal sequence E (n) as an independent variable, using the tested signal S (n) as a dependent variable, carrying out linearity regression least square fitting for an analog-to-digital conversion characteristic curve, thus obtaining a fitting gradient k and an intercept b of a fitting linear formula y=kx+b; substituting the value x obtained by the analog-to-digital converter into the fitting linear formula, calculating a voltage value y applied on the analog-to-digital converter input end, and obtaining the calibrated result. The method and device can improve the analog-to-digital converter calibration precision.

Description

technical field [0001] The invention relates to the technical field of analog-to-digital conversion, in particular to an analog-to-digital conversion calibration method and device. Background technique [0002] With the increasing demand for functional diversity and intelligence of electronic equipment, the complexity of electronic systems is also increasing, and the product development cycle is also facing more severe challenges. The rapid development of integrated circuit technology has increased the A system-level SOC (System-On-Chip) single chip can not only integrate the CPU main control processor, but also integrate memory, analog-to-digital converter (ADC) module, USB module, WIFI, Bluetooth and other The interface module that communicates with the outside greatly reduces the complexity of electronic product system design, shortens the product development cycle, enables various electronic products to be launched on the market faster, and meets people's various needs a...

AI Technical Summary

Problems solved by technology

[0008] For the first method, without considering the characteristics of the ADC itself, all chip sampling values ​​are added to a fixed offset value, the calibration is relatively rough, the calibration accuracy is very low, and sometimes may cause greater errors;

[0009] For the second method, in the testing stage of the electronic system, additional professional testing equipment and reserved test circuits are required, and the testing process of the electronic system needs to be increased. At the same time, due to the non-linearity of the ADC conversion characteristic curve and the instability of sampling The ADC conversion curve cannot be determined by simple two points, so the accuracy after calibration is not high;

[0010] For the third method, in the SOC chip design stage, it is necessary to design complex internal circuits, which not only increases the chip area and increases the chip cost, but also reduces the voltage accuracy of the reference voltage source due to the change of the production process parameter error, and the ADC calibration accuracy It is also difficult to meet expectations

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