# US 8,771,021 B2 · Audio jack with ESD protection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,771,021 B2 - Document ID: US8771021B2 - Status: Granted - Kind: B2 - Application number: 12/910,278 - Filed: 2010-10-22 - Published: 2012-04-26 - Granted: 2014-07-08 - Earliest claimed: 2010-10-22 - Assignees: BlackBerry Limited - Applicants: Wolfgang Edeler - Inventors: Wolfgang Edeler - Web page: https://patentgrep.com/patent/US8771021B2 ## CPC - H01R 13/7031: {Shorting, shunting or bussing of different terminals interrupted or effected on engagement of coupling part, e.g. for ESD protection, line continuity} - H01R 13/6485: {Electrostatic discharge protection (in general H05F1/00, for electric apparatus H05K9/0067)} - H01R 13/7032: {making use of a separate bridging element directly cooperating with the terminals} - H01R 24/58: Contacts spaced along longitudinal axis of engagement - H01R: ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS ## Abstract A plug-and-jack for use with an electronic device that is configured to ensure circuitry of the device is protected from electrostatic discharge. In one case, the jack is an audio jack designed to protect high gain circuitry of the device against electrostatic discharge from the leads of an audio plug. The jack includes a mechanical switch that only connects the high gain circuitry to the appropriate portion of the audio plug once the audio plug is fully inserted. At the same time, the mechanical switch also connects the high gain circuitry and corresponding portion of the audio plug to an electrostatic discharge circuit. ## Claims ### Claim 1 An electronic device, comprising: an audio jack for receiving insertion of an audio plug, the audio plug having two or more plug contacts, each plug contact being separated from the other plug contacts by at least one insulating ring, wherein one of the plug contacts provides an audio signal; an audio subsystem for processing signals, the audio subsystem including a high gain circuit for amplifying the audio signal; and an electrostatic discharge circuit, wherein the audio jack includes an enclosure defining an elongate cavity having an opening at one end, a first jack contact positioned within the cavity, proximate to the opening and connected to the electrostatic discharge circuit, a second jack contact within the cavity disposed further from the opening than the first jack contact so as to contact the plug contact providing the audio signal when the audio plug is fully inserted; and a mechanical switch having an open position and a closed position, wherein the mechanical switch is biased in the open position and wherein the mechanical switch is configured to be moved into the closed position as a result of full insertion of the audio plug, and wherein in the closed position the mechanical switch electrically connects the first jack contact to the second jack contact and electrically connects the second jack contact to the high gain circuit, wherein the mechanical switch comprises a sled with contacts on its ends, and wherein in a first position the sled is closer to the opening than in a second position. ### Claim 2 (depends on 1) The electronic device claimed in claim 1, further including a microphone jack contact within the enclosure but not positioned to directly contact the audio plug, wherein the microphone jack contact is connected to the high gain circuit, and wherein in the closed position the mechanical switch connects the second jack contact to the microphone jack contact. ### Claim 3 (depends on 2) The electronic device claimed in claim 2, wherein the electronic device includes a signal ground insulated from a system ground, and wherein the second jack contact comprises an audio signal jack contact electrically connected to the signal ground. ### Claim 4 (depends on 3) The electronic device claimed in claim 3, further including at least one other jack contact within the cavity disposed further from the opening than the second jack contact, and wherein the at least one other jack contact is connected to the audio subsystem for receiving audio signals for communication to the audio plug. ### Claim 5 (depends on 1) The electronic device claimed in claim 1, wherein the cavity has a longitudinal axis and wherein the sled moves between the first position and the second position in the direction of the longitudinal axis. ### Claim 6 (depends on 5) The electronic device claimed in claim 5, wherein the sled contacts include a first contact, and wherein the first sled contact is positioned to electrically connect the first jack contact, the second jack contact, and the high gain circuit when the sled is in the second position. ### Claim 7 (depends on 6) The electronic device claimed in claim 6, wherein the first sled contact disconnects from the first jack contact, the second jack contact and the high gain circuit in the first position. ### Claim 8 (depends on 1) The electronic device claimed in claim 1, wherein the audio plug comprises a tip-ring-ring-sleeve plug, and wherein, when fully inserted, the first jack contact is positioned to connect with the sleeve of the plug and the second jack contact is positioned to connect with one of the rings of the plug. ### Claim 9 (depends on 1) The electronic device claimed in claim 1, wherein the electronic device comprises a handheld mobile device. ### Claim 10 An audio jack for receiving insertion of an audio plug, the audio plug having two or more plug contacts, each plug contact being separated from the other plug contacts by at least one insulating ring, wherein one of the plug contacts provides an audio signal, the audio jack being configured for use in an electronic device having a high gain circuit for amplifying the audio signal and having an electrostatic discharge circuit, the audio jack comprising: an enclosure defining an elongate cavity having an opening at one end; a first jack contact positioned within the cavity proximate to the opening and adapted for electrical connection to the electrostatic discharge circuit; a second jack contact within the cavity disposed further from the opening than the first jack contact so as to contact the plug contact providing the audio signal when the audio plug is fully inserted; and a mechanical switch having an open position and a closed position, wherein the mechanical switch is biased in the open position and wherein the mechanical switch is configured to be moved into the closed position as a result of full insertion of the audio plug, and wherein in the closed position the mechanical switch electrically connects the first jack contact to the second jack contact and electrically connects the second jack contact to a microphone jack contact adapted for electrical connection to the high gain circuit, wherein the mechanical switch comprises a sled with contacts on its ends, and wherein in a first position the sled is closer to the opening than in a second position. ### Claim 11 (depends on 10) The audio jack of claim 10, wherein the microphone jack contact is positioned within the enclosure but not positioned to directly contact the audio plug, wherein in the closed position the mechanical switch electrically connects the second jack contact to the microphone jack contact. ### Claim 12 (depends on 11) The audio jack claimed in claim 11, wherein the electronic device includes a signal ground insulated from a system ground, and wherein the second jack contact comprises an audio signal jack contact adapted to be electrically connected to the signal ground. ### Claim 13 (depends on 12) The audio jack claimed in claim 12, further including at least one other jack contact within the cavity disposed further from the opening than the second jack contact, and wherein the at least one other jack contact is adapted to be connected to an audio subsystem within the electronic device for receiving audio signals for communication to the audio plug. ### Claim 14 (depends on 10) The audio jack claimed in claim 10, wherein the cavity has a longitudinal axis and wherein the sled moves between the first position and the second position in the direction of the longitudinal axis. ### Claim 15 (depends on 14) The audio jack claimed in claim 14, wherein the sled contacts include a first contact, and wherein the first sled contact is positioned to electrically connect the first jack contact, the second jack contact, and the high gain circuit when the sled is in the second position. ### Claim 16 (depends on 15) The audio jack claimed in claim 15, wherein the first sled contact disconnects from the first jack contact, the second jack contact and the high gain circuit in the first position. ### Claim 17 (depends on 10) The audio jack claimed in claim 10, wherein the audio plug comprises a tip-ring-ring-sleeve plug, and wherein, when fully inserted, the first jack contact is positioned to connect with the sleeve of the plug and the second jack contact is positioned to connect with one of the rings of the plug.