AUDIO ACCESSORY TYPE DETECTION AND CONNECTOR PIN SIGNAL ASSIGNMENT

摘要

An electronic audio host device has an audio accessory connector with multiple pins. An ultrasonic test signal source has an output coupled to a first pin of the connector. A programmable switch circuit couples a second or third pin of the connector, to a ground of the audio host device. A controller measures a signal on one of the pins of the connector while the test signal source is on, and compares the measured signal to a predetermined, stored signature. The signature is associated with one of several different accessory plug pin assignments for the connector, which can be configured using the programmable switch circuit. Other embodiments are also described and claimed.