Offset self-correcting dynamic comparator for successive approximation type analog-to-digital converter

Abstract

The invention discloses an offset self-correcting dynamic comparator for a successive approximation type analog-to-digital converter. A dynamic comparator in a traditional successive approximation type analog-to-digital converter is improved; the dynamic comparator is enabled to perform offset correction, the on-off of NMOS and PMOS is controlled through clock signals generated by the output end of the comparator, and self-correction is performed according to the principle of charge redistribution so that introduction of an amplifier to reduce the static power consumption generated by offset can be avoided, and thus the power consumption of the comparator can be reduced. According to the dynamic comparator, the principle of charge redistribution is effectively utilized; the capacitance values of the correction capacitor and the charging and discharging capacitor can be adjusted to effectively improve the correction precision, and the correction process of the dynamic comparator is separated from the comparison process in the successive approximation type analog-to-digital converter system, so that the influence of the system on the offset correction process is avoided, the offset voltage of the dynamic comparator can be reduced, and the precision of the dynamic comparator is improved.

Description

technical field [0001] The invention belongs to the technical field of analog-to-digital conversion, and in particular relates to an offset self-correcting dynamic comparator for successive approximation analog-to-digital converters. Background technique [0002] In nature, most of the signals generated are macroscopically analog quantities, such as temperature, pressure, sound or touch signals, etc. These signals must eventually be processed in the digital field in many ways, so each system needs an analog Composed of digital converter ADC and digital signal processor DSP. The development of ultra-large-scale integrated circuits has set off a climax in the use of digital processing technology, prompting people to pay attention to the role of interface components between analog and digital systems. Analog-to-digital converters have become a bridge connecting analog signals and digital signals; Today, the analog-to-digital converter is an important part of measuring equipmen...

AI Technical Summary

Problems solved by technology

In order to further improve the performance of the dynamic comparator, it is often required to maintain high-precision performance at high speed, where the offset voltage is directly related to the accuracy of the comparator; the method of reducing the offset in the prior art is to add an amplifier stage before the comparator structure, but adding an amplifier stage increases the power consumption of the system and also affects the speed of the comparator

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