Audio I O headset plug and plug detection circuitry

• US 8,467,828 B2
• Filed: 03/01/2011
• Issued: 06/18/2013
• Est. Priority Date: 01/05/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Johnson, Timothy, Pantfoerder, Achim
• Primary Examiner(s): Nguyen, Tu X
• Application Number:
  US13/038,172
• Publication Number:
  US 20110150234A1
• Time in Patent Office: 840 Days
• Field of Search: 455/556.1, 455/557, 455/575.2
• US Class Current: 455/556.1
• CPC Class Codes: H01R 13/703 operated by engagement or disengagement of coupling parts, e.g. dual-continuity coupling partH01R13/71 takes precedence
• CPC Class Codes: H01R 2201/16 for telephony
• CPC Class Codes: H01R 24/58 Contacts spaced along longitudinal axis of engagement
• CPC Class Codes: H01R 29/00 Coupling parts for selective co-operation with a counterpart in different ways to establish different circuits, e.g. for voltage selection, for series-parallel selection, programmable connectors
• CPC Class Codes: H04M 1/6058 involving the use of a headset accessory device connected to the portable telephone
• CPC Class Codes: H04M 1/72409 by interfacing with external accessories hands-free H04M1/60
• CPC Class Codes: H04M 1/72412 using two-way short-range wireless interfaces
• CPC Class Codes: H04R 1/1041 Mechanical or electronic switches, or control elements switches in general H01H
• CPC Class Codes: H04R 29/00 Monitoring arrangements; Testing arrangements for hearing aids H04R25/30; detection of loudspeaker connection H04R5/04; sound-field adaptation dependent on speaker detection H04S7/308
• CPC Class Codes: H04R 3/00 Circuits for transducers , loudspeakers or microphones

Abstract

A single prong, multiple signal conducting plug and plug detection circuitry is provided. The plug may be electrically coupled to a stereo headset including a microphone. The plug may include four signal conducting regions arranged in a predetermined order along the length of the prong. Detection circuitry may be operative to determine whether a microphone type of plug (e.g., a four region plug including a microphone region and two audio regions, or a three region plug including microphone region and only one audio region) or a non-microphone type of plug (e.g., stereo plug) is inserted into the jack of an electronic device (e.g., mobile phone). Detection circuitry may also detect user activated functions performed in response to user activation of one or more switches included with the headset. For example, the headset may include a single switch for performing a function with respect to a microphone (e.g., end-call function).

Claims

1. A system for detecting a type of plug to be received by a portable electronic device, the system comprising:

a jack constructed to receive a plug selected from at least a microphone type and a non-microphone type, wherein the jack comprises at least a microphone connector electrically coupled to microphone detection circuitry, and a ground connector coupled to a ground source;

the microphone detection circuitry operative to determine whether the received plug is the microphone type or the non-microphone type, the microphone detection circuitry including;

a bias power source to be applied to the microphone connector while the plug is detected in the jack, wherein the microphone connector is coupled to the bias power source;

a transistor whose control electrode is coupled to the microphone connector, and whose output electrode provides a signal which indicates whether the received plug is the microphone type or the non-microphone type;

a separate HEADSET DETECT signal that indicates whether a plug is received by the jack;

headset switch detection circuitry to monitor the microphone connector for a headset switch activation event and provide a further signal in response to a monitored headset switch activation event executed by a headset switch; and

wherein the headset switch is a first headset switch, wherein the headset switch activation event is a first headset switch activation event, wherein the microphone is electrically connected to a second headset switch, the headset switch detection circuitry to;

monitor the plug for a second headset switch activation event executable by the second headset switch;

change a state of the further signal in response to a monitored first headset switch activation event; and

change a state of the further signal in response to a monitored second headset switch activation event.

2. The system of claim 1, wherein the jack comprises a headset detect switch electrically coupled to a power source and at least one of a right and a left connector of the jack, and further comprising a node coupled between the headset detect switch and the power source, the node provides the separate HEADSET DETECT signal that indicates whether a plug is received by the jack.

3. The system of claim 1, wherein the bias power source is to monitor the HEADSET DETECT signal and provide a bias power signal to the transistor in response to the HEADSET DETECT signal.

4. The system of claim 1, wherein the headset switch activation event is one of an open circuit event and a short circuit event.

5. The system of claim 1, wherein the bias power source is to:

if the received plug has a microphone region in an anticipated microphone region, provide the bias power to a transistor operative to provide the signal; and

if the received plug does not have a microphone region in the anticipated microphone region, electrically coupling the transistor to ground.

6. The system of claim 1, wherein the detection circuitry is operative to cease supplying the microphone bias voltage after the plug is removed.