Low power approach detection device

摘要

A proximity detection device with a detection circuit is provided. The detection circuit is configured to receive an approach signal indicative of a first voltage level and a reference signal indicative of a second voltage level, and to receive a wake-up signal at predetermined intervals. The sensing circuit is further configured to compare the first voltage level to the second voltage level in response to the wake-up signal and to generate a first output indicative of an external power source electrically coupled to a vehicle to one or more batteries in the vehicle based on the comparison of the first voltage level with the second voltage level to load.