Dynamic comparer

Abstract

The invention discloses a dynamic comparator including a preamplifier and a positive feedback latch with drive, the preamplifier is controlled by the clock signal CLK and the asynchronous control signal reset, the positive feedback latch with drive is controlled by CLK; when the CLK is in low level, the reset is in high level, tubes connecting two output ends of the preamplifier are cut off, the preamplifier performs amplification for the input signal, the positive feedback latch is reset; when the CLK is in high level, the tail current tube of the preamplifier is cut off and the output end and the load of the preamplifier are cut off, the positive feedback latch works, when the positive feedback latch outputs the compared result, the reset is in the low level, tubes connecting the output end of the preamplifier are closed to make the output end of the preamplifier reset. The invention improces speed of the clock control preamplifier, makes the comparator work in higher frequency and greatly reduces feedback noise of the dynamic comparator, under condition of having advantage of low power dissipation of traditional dynamic comparator.

Description

technical field [0001] The invention relates to the technical field of comparators in analog-to-digital converters, in particular to a dynamic comparator, which has the advantages of high speed, low power consumption, low offset voltage and low kick back noise. Background technique [0002] The comparator is an important module of the analog-to-digital converter. The characteristics of the comparator, such as offset voltage, speed, and power consumption, have an important impact on the accuracy, speed, and power consumption of the entire analog-to-digital converter. [0003] Commonly used comparators include static comparators and dynamic comparators. The offset voltage and feedback noise of the static comparator are small, but due to the quiescent current in the pre-amplifier and the latch, the general power consumption is relatively large, and the typical static comparator has a static DC current at the output node, which will affect the reset speed. [0004] The traditi...

AI Technical Summary

Problems solved by technology

The offset voltage and feedback noise of the static comparator are small, but due to the static current in the pre-amplifier and the latch, the power consumption is relatively large, and the typical static comparator has a static DC current at the output node, which will affect the reset speed

[0004] The traditional dynamic comparator usually uses a clock signal to control the pre-amplifier and the latch, so the power consumption is relatively low, but there is a very large transient current, resulting in relatively large feedback noise, and because the pre-amplifier works under clock control , operating slower than the pre-amplifier in the static comparator

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