1. An apparatus comprising: a first sensor for producing a continuous analog signal while monitoring a first physical condition during a first time interval, wherein the continuous analog signal is digitized to produce a first signal having data that is indicative of the first physical condition, and wherein the data is classified into a first voltage range among a plurality of voltage ranges; a first processor for: i) processing the data conveyed by the first signal, resulting in the first processor transitioning from a first data-processing state to a second data-processing state, wherein the transitioning of the first processor is based on a predetermined first pattern being detected by the first processor in the data conveyed by the first signal, and wherein the predetermined first pattern is learned by the first processor based on a second signal that is generated in response to having monitored the first physical condition prior to the first time interval, and ii) generating a third signal, wherein the third signal is based on the transitioning of the first processor to the second data-processing state; and a second processor for receiving the third signal from the first processor and for processing at least a portion of the data conveyed by the first signal, according to a first power mode indicated by the third signal received from the first processor; wherein the first processor is also for generating the first pattern, wherein the first processor generates the first pattern before processing the first signal, wherein the first pattern is based on the second signal, and wherein the second signal is based on the monitoring of the first physical condition.