Comparator with adjustable reference voltage

Abstract

The invention provides a comparator with adjustable reference voltage, which is applied to sub digital-analog conversion module design in digital-analog conversion circuits in high-speed pipelines. Based on a traditional capacitive divider comparator with adjustable reference voltage, the invention proposes a pre-chargeable capacitive divider comparator to conveniently adjust the judgment threshold voltage of the comparator. Compared with a traditional capacitive divider comparator with adjustable reference voltage, the pre-chargeable structure reduces the judgment threshold level offset voltage of the comparator, and relieves a series of design difficulties caused by over high or over low judgment threshold voltage in traditional structure.

Description

technical field [0001] The invention relates to a comparator with adjustable reference voltage, which is mainly aimed at high-speed and high-precision analog-to-digital conversion circuits and analog front-end interface circuits of various modern communication and signal processing systems. Background technique [0002] The invention relates to a comparator with adjustable reference voltage, which is mainly aimed at high-speed and high-precision analog-to-digital conversion circuits and analog front-end interface circuits of various modern communication and signal processing systems. [0003] The rapid development of deep submicron integrated circuit technology and handheld mobile device industry has brought unprecedented prosperity to the global electronics market. Handheld mobile devices include handheld communication entertainment and portable medical equipment, etc., which have a very broad market potential and development prospects. Products with stronger functions and...

AI Technical Summary

Problems solved by technology

[0008] But the capacitive voltage divider reference voltage adjustable comparator also has some disadvantages

The decision level of the comparator is a uniformly distributed voltage value between the reference levels, because the decision level of the comparator is related to the ratio of the reference voltage and the capacitance. When the voltage value is in the middle of the reference level, the ratio of the capacitance Roughly the same, so the influence of the parasitic capacitance of the switch on the charging capacitance is roughly the same, and the judgment level of the comparator is less affected; but when the voltage value is between the reference levels and close to the two reference levels, the ratio of the capacitance is different Larger, so the parasitic capacitance of the switch has a great impact on the charging capacitor, and the judgment level of the comparator is greatly affected, resulting in a larger offset voltage

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