Low-voltage asynchronous successive approximation analog-to-digital converter

Abstract

The invention discloses a low-voltage asynchronous successive approximation analog-to-digital converter and a conversion method. The analog-to-digital converter comprises: a sampling network, a capacitance array pulse width modulation time domain comparator and a logic control circuit. The sampling network of a capacitor array uses a bootstrapping switch. A size of the capacitance in the capacitance array is decreased progressively as a two times relation. All top crowns of capacitors and the bootstrapping switch are connected and output to the comparator. The time domain comparator comprises: a pulse width modulation unit and a trigger. And the time domain comparator is used to compare sizes of output voltages of the capacitor array. In the logic control circuit, the asynchronous sequence is used to make the capacitor array complete switching successively. A power consumption efficiency of the analog-to-digital converter can be effectively improved. A peripheral circuit demand can be reduced. The analog-to-digital converter and the method can be used in an advanced-technology ultra low power supply voltage design.

Description

technical field [0001] The present invention relates to a low-voltage asynchronous successive approximation analog-to-digital converter, in particular to a successive approximation analog-to-digital converter which uses a time-domain comparator, is suitable for deep submicron low power supply voltage, and improves power consumption efficiency and reduces peripheral circuit requirements through asynchronous sequence control. approximation to the analog-to-digital converter. technical background [0002] The high power efficiency of successive approximation analog-to-digital converters in 8-10 bit precision and sampling rates below 100 MHz distinguishes it from other types of analog-to-digital converters, and the ultra-low power consumption requirements of handheld and portable devices further promote Wide application of such analog-to-digital converters. [0003] Compared with the synchronous timing type, the successive approximation analog-to-digital converter of asynchrono...

AI Technical Summary

Problems solved by technology

[0005] The design of traditional analog circuits under deep submicron low voltage is subject to many restrictions: the signal amplitude decreases, which increases the requirements for analysis and comparison accuracy; the intrinsic gain of the tube decreases; the leakage current increases; the complex high-gain structure is no longer applicable, etc.

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