Abstract: This document discusses, among other things, a detection system configured to identify a type of a pole of a four-pole audio jack using first and second comparators. The detection system can include a bias circuit configured to bias a detection input coupled to the pole, and first and second comparators configured to compare the detection input to respective first and second thresholds to provide an indication of the type of the pole.

Abstract: This application discusses, among other things, multiple interface detection circuits configured to connect with a mobile electronic device connector. In an example, a multiple interface detection circuit can include a first comparator to compare a bus voltage of the mobile electronic device connector with a first threshold and to provide a first control signal, a second comparator to compare the bus voltage of the mobile electronic device connector with the first threshold and to provide a second control signal, a third comparator to compare the bus voltage of the mobile electronic device connector with a second threshold and to provide a third control signal, and a switch control configured to switch one or more signals of the connector.