Charge sharing type analog-to-digital converter quantification method based on dynamic tracking

Abstract

The invention discloses a charge sharing type analog-to-digital converter quantification method based on dynamic tracking. According to the method, the difference of code words between two sampling points is quantified, the capacitor switching direction is judged according to the comparison result of a comparator, the interval where the sampling points are located is searched in a binary increasing or decreasing mode until the comparison result is reversed, the interval where the sampling points are located is determined, and new prediction code words and final output code words are obtained;the DAC module adopts a charge sharing switching mode, only one group of capacitor array is needed, the capacitor array is simplified, and the power consumption is reduced; two groups of capacitor substitution arrays are introduced when prediction is inaccurate, and 1-2 capacitors are used for switching at most except the capacitor substitution arrays in the quantization process, so that differential nonlinear DNL can be improved, and the power consumption of the analog-to-digital converter is reduced on the whole. The method is particularly suitable for temperature sensor signals which are slow in sensor signal amplitude change and do not change suddenly, and the comparison frequency of the comparator and the capacitor array switching frequency of the DAC can be greatly reduced.

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...

AI Technical Summary

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

Images