Asynchronous Low-Power Analog-to-Digital Converter Circuit With Configurable Thresholds

摘要

An analog-to-digital converter circuit is described that includes register space to keep one or more values to establish upper and lower thresholds of the analog-to-digital converter. The analog-to-digital converter circuit also includes first and second comparators to compare an analog input signal against the upper and lower thresholds and to trigger an analog-to-digital conversion process in response to the analog input signal crossing one of the thresholds. The analog-to-digital converter circuit also includes first logic circuitry to discard a result of the analog-to-digital conversion process if the result is within a prior analog-to-digital conversion process's thresholds. The analog-to-digital converter circuit also includes second logic circuitry to provide the result as an output and generate an interrupt if the result is not within the prior analog-to-digital conversion process's thresholds.

主权项

1. An analog-digital-converter comprising:
a first comparator and a first digital-to-analog converter, the first digital-to-analog converter coupled to a first reference input to the first comparator; a second comparator and a second digital-to-analog converter, the second digital-to-analog converter coupled to a second reference input to the second comparator; register space coupled to both the first and second digital-to-analog converters, the register space to help establish and store upper and lower thresholds for the first and second comparators that are respectively applied to the first and second reference inputs; and, an analog input signal node to provide an analog input signal to both the first and second comparators, the first and second comparators to trigger a next analog-to-digital conversion process in response to the analog input signal crossing either of their respective thresholds; analog-to-digital conversion circuitry to determine a digital value representative of said analog input signal in response to said trigger; and, circuitry to generate an interrupt commensurate with said digital value.