Enable and disable comparator voltage reference

摘要

This document discusses, among other things, systems and methods to reduce power use of an accessory detection device. The accessory detection device can be configured to be coupled to a mobile device having an audio jack configured to be coupled to a mobile device accessory having a send/end key. In an example, the accessory detection device can include a comparator and a switch. The comparator can be configured to receive mobile device accessory information from the mobile device accessory and to determine activation of the send/end key using the received mobile device accessory information. The switch can be configured to receive connection information indicative of mobile device accessory connection to the audio jack and to isolate a reference input of the comparator from a supply voltage using the connection information, for example, to reduce leakage current.

主权项

1. A system comprising:
an accessory detection device configured to be coupled to a mobile device having an audio jack, wherein the audio jack is configured to be coupled to a mobile device accessory having a send/end key, the accessory detection device including:
a comparator configured to receive mobile device accessory information from the mobile device accessory and to determine activation of the send/end key using the received mobile device accessory information; anda switch configured to receive connection information indicative of a mobile device accessory connection to the audio jack and to isolate a reference input of the comparator from all supply voltage using the connection information.