A Quantization Method for Charge-Sharing Analog-to-Digital Converter Based on Dynamic Tracking

Abstract

A charge-sharing analog-to-digital converter quantization method based on dynamic tracking, the present invention determines the capacitance switching direction by quantizing the difference between the code words between two sampling points, and the capacitance switching direction is determined by the comparison result of the comparator. Find the interval where the sampling point is located in a small way until the comparison result is reversed, determine the interval where the sampling point is located, and obtain a new predicted codeword and the final output codeword; the DAC module adopts the charge sharing switching method, only a set of capacitor arrays are needed, simplifying The capacitor array is used to reduce power consumption; when the prediction is inaccurate, two sets of capacitor replacement arrays are introduced. In the quantization process, in addition to the capacitor replacement array, there are at most 1 to 2 capacitors to switch, which can improve the differential nonlinear DNL, ​​from the overall The power consumption of the analog-to-digital converter is reduced; the invention is especially suitable for the temperature sensor signal whose signal amplitude changes slowly and does not change suddenly, and can greatly reduce the comparison times of the comparator and the switching times of the capacitance array of the DAC.

Description

technical field [0001] The invention belongs to the technical field of analog integrated circuits, and relates to a dynamic tracking-based charge-sharing analog-to-digital converter quantization method, which is suitable for quantizing sensor signals such as temperature whose amplitude changes slowly and does not change abruptly. Background technique [0002] Sensor signals such as temperature have the characteristics of slow amplitude changes and no sudden changes. When quantifying signals such as temperature, the difference between two adjacent sampling points is usually very small, so the interval prediction algorithm can be used for quantization to achieve low-power conversion. [0003] The traditional interval prediction algorithm loads the high bits of the last quantization result directly into the high bits of this quantization, and then judges whether the prediction is correct by switching redundant capacitors. If the prediction is correct, only the low-order codewo...

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Problems solved by technology

[0006] Aiming at the problems of energy waste caused by prediction and judgment errors in the above-mentioned traditional interval prediction algorithm and the problems of simultaneous switching of multiple capacitors and code word overflow in the existing code word recombination and quantization methods, the present invention proposes a charge sharing model based on dynamic tracking. The digital converter quantization method introduces two capacitor replacement arrays when the prediction is inaccurate, switches the second capacitor replacement array according to the charge-sharing switching method, and no longer controls the capacitor array through the generated binary codeword, avoiding codeword overflow At the same time, due to the use of a charge-sharing capacitor array, the DAC module does not need to set up two sets of DAC capacitor arrays, which can further reduce power consumption and make the capacitor array more streamlined

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