KR20110046361A - How to Detect Attachments with Audio Jacks - Google Patents

Abstract

PURPOSE: A detecting method of a sub device is provided to automatically recognize the type of an audio jack connector to a host device and to detect the presence of a subsystem by interacting with a host device. CONSTITUTION: An audio/video jack connector(205) accepts an audio/video jack plug. The audio/video jack connector includes an electrical contact. A detection circuit(215) is connected to the audio/video jack connector. The detection circuit detects a resistance corresponding to resistive load to the audio/video jack connector. A processor(235) distinguishes the function of the other device according to the determination of the detection circuit.

Description

How to detect an accessory with an audio jack {METHOD OF DETECTING ACCESSORIES ON AN AUDIO JACK}

The present invention automatically detects which device is connected to a host device, and more particularly relates to a system and method that can detect the presence and type of an accessory device by interaction with the host device.

There are many types of electronic devices that can be used to manage personal information and provide personal media entertainment. Some of them play audio media and video media such as slide shows, music, movies or other video programs. These include personal computers, personal digital assistants (PDAs), MP3 players, cell phones, and the like. The user needs different device capabilities based on the different types of media included and wants to connect and match the media player with the accessory. To provide an accessory device, a user may need a basic level of skill for determining device compatibility and interconnecting multiple devices.

A audio / video jack connector configured to accept an audio / video jack plug from another device, a detection circuit in electrical communication with the audio / video jack connector, and detection An apparatus is provided that includes a processor in electrical communication with a circuit. The audio / video jack connector includes an electrical contact for connection to a connection terminal of the audio / video jack plug. The detection circuit is configured to determine the resistance at the connection terminal. The resistor is the resistive load of another device at the connection terminal of the audio / video jack plug. The processor is adapted to identify the function of another device according to the determined resistance and to set the operation of the device according to the determined function.

Detecting whether the audio / video jack plug of the first device is inserted into the audio / video jack connector of the second device, and determining the resistance at one or more connection terminals of the audio / video jack plug using the second device And identifying, using the second device according to the resistance at the one or more connection terminals, a function that can be performed by the first device, and according to the identified function that can be performed by the first device. 2 provides a method comprising the step of setting the device.

This description is intended to provide an overview of the subject matter of the present patent application and is not intended to provide an exhaustive or exhaustive description of the invention. The details are intended to provide further information regarding the present patent application.

The drawings are not necessarily to scale, and like parts may represent like parts in the various drawings. Similar reference numerals but different subscripts may indicate different cases of similar components. The drawings are for the various embodiments described herein and are not intended to limit the invention.
1 shows an example of an audio / video jack plug.
2 is a block diagram illustrating a portion of an example of a device for automatically detecting the presence and type of a connected accessory device.
3 is a block diagram showing a part of a detection circuit.
4 is a flowchart illustrating an example of a method for automatically detecting the presence of an accessory device when the accessory device is connected to a host device.
5 is a flowchart illustrating another example of a method for automatically detecting the presence of an accessory device when the accessory device is connected to a host device.
6 is a flowchart illustrating an example of a method for automatically detecting the presence of an accessory device when the accessory device is connected to the host device and identifying the operation of the requested host device.

The present invention generally relates to systems and methods for automatically detecting the presence and type of an accessory when the accessory connects to the host device.

1 shows an example of a jack plug of an audio jack connector or a video jack connector. This audio jack connector or video jack connector is sometimes called a TRS connector. "TRS" stands for tip, ring and sleeve conduting terminals. In some examples, the audio jack connector or video jack connector may be a TS connector having only a tip and sleeve connection terminal. In the example shown in FIG. 1, the audio jack connector or video jack connector has four connection terminals and may be referred to as a TRRS connector for tip, ring, ring, and sleeve connections.

Jack plugs may be included as part of several types of devices such as headsets, microphones, and audio visual (A / V) cables. Such devices are typically accessory devices that plug into a host device such as a media player or computing device. The user will have to program or otherwise uniquely configure the host device for each type of accessory device plugged into the host device. It would be convenient for the host device to automatically recognize the type of device that is plugged into the audio jack connector or the video jack connector.

Table 1 shows an example of a signal map for four terminal jack plugs, such as the jack plug shown in FIG. For example, as shown in the top row, if the accessory is a stereo headset with a microphone (MIC), terminals 1 and 2 of the plug can be used for left audio and right audio, respectively, and terminal 3 is the microphone. Can be used for connection. The signals are connected to terminal 4 (eg grounded).

The terminals of the jack plugs will be connected to various types of circuits depending on the function of the accessory. Because of these various circuits, the impedance measured at the terminals of the jack plugs will vary depending on the function of the accessory.

      Accessories   Terminal 1   Terminal 2   Terminal 3   Terminal 4 Stereo Headset with MIC Left audio Right audio     MIC     GND Mono Headset with MIC Mono audio Mono audio     MIC     GND       Standard 3.5mm headset Left audio Right audio     GND     GND          A / V cable Left audio Right audio    video     GND

Table 2 shows an example of how the impedance measured at the terminals can be used to determine the type of accessory equipment plugged into the audio jack connector or video jack connector. For example, if the impedance measured at terminal 1 or terminal 2 is approximately 600 ohms or less, the accessory includes a headset. If the measured impedance determines that terminal 1 or terminal 2 are shorted together, the accessory is a mono-headset. Likewise, if the impedance measured at terminal 3 is about 75 ohms, the accessory comprises a television. If the impedance measured at terminal 3 is in the range of approximately 1.1 kΩ to 2.2 kΩ, the accessory shall include a microphone. A plurality of resistors may be used to indicate a plurality of functions of an accessory such as a headset in which the microphone is represented by terminal 1 and / or terminal 2 and terminal 3.

The measured impedance can also be used to determine the presence of a jack plug. For example, a jack plug can be detected when the value of the impedance of any terminal is less than 500 kΩ. In another example, a jack plug can be detected when the value of the impedance of any terminal is less than 10 kΩ.

        Terminal number Measured impedance       Device ID           1 and 2 Less than 600Ω
1 and 2 shorted
1 and 2 not shorted headset
Mono headset
Stereo headset           1 and 2         Over 500 kΩ          Opening             3            GND Short-SEND / END Press
Or standard headset             3            75Ω           TV             3      1 kΩ to 2.2 kΩ        microphone             3      4kΩ to 500kΩ       Button Press Options             3         Over 500 kΩ           Opening

2 is a block diagram of portions of an example of a device 200 that automatically detects the presence and type of accessory device being connected. The device 200 includes an audio jack connector or video jack connector 205 that receives an audio jack plug or a video jack plug of a separate accessory device. The connector 205 includes an electrical contact for connection with a connection terminal of the plug.

In a particular example, the connector 205 includes two electrical contacts 210A and 201B that receive a TS type connector plug. In a particular example, the connector 205 includes three electrical contacts 210A, 201B, 201C that receive a TS type connector plug. In a particular example, the connector 205 includes four electrical contacts 210A, 201B, 201C, and 201D that receive a TRRS type connector plug.

The device also includes a detection circuit 215 electrically connected with the connector 205. The detection circuit 215 determines the resistance or impedance at one or more connection terminals of the jack plug. The determined resistance is the resistive load of a separate accessory visible at the connecting terminal of the plug, not just the resistance of the connecting terminal.

3 is a block diagram of portions of an example of detection circuit 315. Resistors and capacitors (R _PIN and C _PIN ) represent the impedance seen at the connecting terminals of the jack plugs. The detection circuit 315 also includes a controllable current source 320 and a comparator 325. The current source 320 outputs a current (e.g., source and sink) proportional to the digital value idac [9: 0] of the identification register. To determine the resistance of the connection terminal, the detection circuit 315 converts (eg, increases) the digital value of the resistor to provide a proportional current to the R _PIN to provide a voltage V _PIN at the input of the comparator 325. Create When V _PIN is approximately equal to V _REF , the detection circuit generates a detection signal. The value of R _PIN is determined from the known value of V _REF and the current value corresponding to the digital value in the identification register.

The terminal capacitance C _PIN and the internal capacitance of the connection C _INT are the combined capacitances seen at the connecting terminals. Because of this capacitance, there is a time constant associated with the voltage V _PIN reaching its final value. The time for the V _PIN to reach 50% of its final value is 0.7R _PIN * (C _PIN + C _INT ). The detection circuit allows sufficient time for the V _PIN to stabilize between the measurements before changing the value of the identification register. In a particular example, the resistance of the plurality of connecting terminals is determined by using a switch circuit that switches different terminals to the detection circuit input using the same detection circuit 315. In a particular example, different detection circuits 315 are included for each connection terminal.

Referring to FIG. 2, the device 200 also includes a processor 235 that is telecommunicationally coupled to the detection circuit. The telecommunications connection allows the processor 235 and the detection circuit 215 to communicate signals even though there is an arbitration circuit. In some examples, processor 235 is a microprocessor. In some examples, processor 235 is an application specific integrated circuit (ASIC). The processor 235 executes instructions in software and / or firmware to perform built-in functions. Software and / or firmware are contained within the module. One module can perform more than one function.

Processor 235 identifies the function of the separate accessory device according to the determined resistance. In a particular example, when the detection circuit 215 is the detection circuit 315 of FIG. 3, the processor 235 identifies the function of that separate device according to the value of the identification register. Processor 235 then sets up the operation of device 200 in accordance with the determined function.

For example, the connector 205 may include a first electrical contact 210A for connection with the first connection terminal of the plug, and a second electrical contact 210C for connection with the second connection terminal of the plug. Can be. Using the examples in Table 2, if the processor determines that the measured resistance of at least one of the two connection terminals is 600 Ω, the accessory device comprises a headset and the processor 235 sends the audio signal to the connection terminal. Set to provide. If the processor 235 determines that the electrical contacts are shorted together (eg, by connecting electrical contacts to the inputs of the detection circuit 215), the accessory device is identified as being a mono-headset. If the processor determines that the electrical contacts are not shorted, the accessory is identified as being a stereo-headset and the processor 235 provides a stereo audio signal to the connection terminal.

In some examples, device 200 includes a media player. Processor 235 is a baseband processor and device 200 includes an audio codec module 240. The processor 235 sets the audio codec module 240 according to the determined function of the separate accessory device. In a particular example, the processor 235 sets the audio codec module 240 to provide a mono audio signal or a stereo audio signal to the connection terminal of the plug depending on whether the determined function is mono audio or stereo audio.

The device 200 is not limited to providing audio information. In some examples, processor 235 may determine an accessory including the microphone (eg, by measuring a resistance in the range of 1 kV to 2.2 kV at the third connection terminal in the example of Table 2). The processor 235 configures the audio codec module 240 to receive an audio signal from a connecting terminal of the plug according to the measured resistance.

The function detectable by the device 200 is not limited to the audio function. Accessory equipment includes a video display or monitor. In some embodiments, device 200 includes video processor 245. The processor 235 may determine whether the accessory includes video capability (eg, by measuring a resistance of about 75Ω at the third connection terminal in the example of Table 2). The processor 235 sets the video processor 245 to provide video information to the connection terminal of the plug.

4 is a flow diagram illustrating an example of a method 400 for automatically detecting the presence of an accessory device when the accessory device is connected to a host device. In step 405, the first device

Detects when the audio / video jack plug is inserted into the audio / video jack connector of the second device. In this way, the second device automatically detects the presence of the first device. In some instances, this occurs when current begins to flow in the detection circuit due to the presence of the connecting terminal to generate a voltage V _PIN that is less than the threshold voltage (eg, V _REF ).

In step 410, the resistance of at least one connection terminal of the plug is determined using the second device. This resistance includes the resistive load of the first appliance which is measurable at the connecting terminal of the plug. In step 415, a function that the first device can perform is identified by the second device according to the resistance at the at least one connection terminal. In step 420, the second device automatically sets itself according to the function that can be performed by the identified first device.

Returning to FIG. 2, according to some examples, device 200 includes control logic circuit 250 that is in electrical communication with processor 235. The processor 235 sets the device 200 by using the control logic circuit 250 to change the state of the switches in the device 200, for example. In some examples, control logic circuit 250 communicates information with processor 235 using an inter-integrated circuit protocol (I ² C). The device 200 includes an I ² C slave module 255 for communicating with the processor 235.

5 is a flow diagram illustrating an example of a method 500 for automatically detecting the presence of an accessory device when the accessory device is connected to a host device. In step 505, the device 200 of FIG. 2 detects from the measured impedance whether the user connected the jack plug of the accessory device to the connector of the device 200.

In step 510, a resistance is determined that makes it possible to identify the function of the accessory device. In some examples, control logic circuit 250 changes the digital value of the identification to change the measured current used by detection circuit 215. When a detection signal is received from the detection circuit 215, the value stored in the identification register of the control logic circuit 250 represents a function.

In step 515, the control logic circuit 250 generates an interrupt to the processor 235 when the resistance is determined by the detection circuit 215. This interrupt can be sent via the I ² C slave module 255 using the I ² C protocol. In step 520, the processor 235 reads the value from the identification register. In some examples, processor 235 reads an identification register from I ² C slave module 255.

In step 525, the processor 235 determines (eg, reads) the function of the accessory device using the value in the identification register. For example, the processor 235 can determine whether the accessory includes a headset, a stereo headset, a microphone, or a video display. The processor 235 sets the device 200 according to the identified accessory device information. For example, when determining that the accessory device is a headset, the processor 235 sets the control logic circuit 250 to switch the audio information to the connection terminal, for example, by switching the switch multiplexer 260. The processor 235 sets the control logic circuit 250 to switch the video information to the connection terminal, for example, by the switch 265 when it is determined that the accessory device displays the video. When the processor 235 determines that the accessory device includes the microphone, the control logic circuit 250 may, for example, switch 265 to route the audio information from the connection terminal to the audio codec module 240. Set.

In some instances, the accessory may change the resistance that appears at one or more connection terminals. For example, the accessory device may include a switch for changing the resistance at the connection terminal of the jack plug, for example, when the user activates the switch by pressing a button. In some instances, the resistance at the connection terminals only changes while the user activates this switch (eg, pressing a button).

In some instances, the detection circuit 215 first determines the resistance that appears at the connecting terminal of the jack plug and then detects the change in the determined resistance. As a result of detecting this change, a process interrupt is generated by the control logic circuit 250. In some examples, processor 235 receives a value indicative of a resistance determined in association with the interrupt, for example from an identification resist. The processor 235 changes the operation of the device 200 according to the detected change in the resistance. In some examples, processor 235 initiates the identified operation in accordance with the received value.

As an illustrative example, assume that the initial resistance determined by the detection circuit 215 enables the accessory device to identify that it includes a headset. Thereafter, the resistance is changed at this initial resistance and the detection circuit 215 provides the processor 235 with the value of the resistance. Based on this resistance value, processor 235 then initiates operation of device 200 based on that value, such as, for example, stop, play, rewind, or fast forward. The list of possible examples of resistors for this operation includes, but is not limited to, 4 kW for stop, 5.62 kW for regeneration, 7.87 kW for rewind, and 11 kW for fast forward. Other actions may include pausing, skipping, going back, and decreasing or raising the volume. In another example, the accessory device includes a video display or monitor and the operations include menu operations such as selection, skipping, playback, fast forwarding, and the like.

Different resistance values can be switched for one or more connection terminals to identify different operations of the same accessory. In some embodiments, multiple keys of a headset with a keypad can be monitored. This is useful for controlling the media player of the host device. In some instances, the resistance change is only apparent while the user presses the button and returns to the original resistance when the button is no longer pressed. The device 200 can detect the stuck state of the switch by monitoring the amount of time the change in resistance is apparent.

In some examples, device 200 includes sensing circuitry 270 in electrical communication with control logic circuit 250 to detect the presence of a plug. The detection circuit 215 detects a change in resistance at the connection terminal, and the detection circuit 270 detects whether the plug is still connected. Processor 235 then initiates operation of the device in response to the detected change in resistance.

6 is a flow diagram illustrating an example of a method 600 for automatically detecting the presence of an accessory device and identifying a requested device operation when the accessory device is connected to a host device. In step 605, the device 200 of FIG. 2 detects whether the user connected the audio / video jack plug of the accessory device to the connector of the device 200 based on the measured impedance. The measured impedance is shown at the connecting terminal of the jack plug, and in step 610, the host device identifies the type of accessory device by the measured impedance.

In step 615, the detection circuit 215 detects a change in resistance of the connection terminal of the jack plug. The change may appear at the same connection terminal used to identify the device, or the impedance change may appear at different connection terminals of the jack plug. The change may be due to the user pressing a button on the accessory or the user activating a switch on a wire or cable attached to the jack plug.

In step 620, an interrupt is generated when the resistance value is determined. This interrupt may be sent to the processor 235 of the device 200 using the I ² C protocol. Processor 235 then reads the value corresponding to the resistor, for example by reading an identification register.

In step 625, the processor 235 identifies the action corresponding to the resistance caused by the button press or switch activation. Processor 235 then begins its operation. When the operation is complete, the device waits for the next resistance change to signal the next device operation. It can be seen that this impedance monitoring detects the type of accessory that the host device is connected to, allowing the host device to set itself up appropriately, and allowing the host device to keep track of the status change of the accessory device.

Additional notes

The above description includes references to the accompanying drawings, which form a part of the detailed description of the present specification. The drawings show, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are also referred to herein as "examples." All publications, patents, and patent documents mentioned in this application are incorporated by reference in their entirety, as if each were incorporated by reference. In the event of a discrepancy between the usage of this application and the aforementioned documents by inclusion by reference, the usage of the included document (s) should be considered as a supplement to the usage of this application; In the case of irreconcilable inconsistencies, the usage herein is governed.

In this application, the term "or" is non-exclusive, that is, unless otherwise specified, "A or B" refers to "A not B", "B not A", and "A and B". Used to grow. Also in the appended claims, the term “comprising” is open-ended, ie a system, apparatus, article comprising elements other than those listed before this term in the claims. (article), or process is still considered to be within the scope of the claims. In addition, in the following claims, the terms "first", "second", "third", and the like are used only as labels, and are not intended to add numerical requirements to the object.

The method examples described herein may be implemented at least partially in a machine or computer. Some examples may include a computer readable medium or a machine readable medium encoded with instructions operative to configure an electronic device for performing the methods as described in the examples above. Implementation of these methods may include code, such as microcode, assembly language code, higher-level language code, and the like. Such code may include computer readable instructions for performing various methods. The code may form part of a computer program product. In addition, the code may be stored tangibly on one or more volatile or nonvolatile tangible computer readable media, eg, during execution or at other times. Examples of such real computer readable media include hard disks, removable magnetic disks, removable optical disks (eg, compact disks and digital video disks), magnetic cassettes, memory cards or sticks, RAM, ROM, and the like. But it is not limited thereto.

The above description is for illustrative purposes and is not intended to be limiting. In other examples, the examples described above (or one or more of their aspects) can be used in combination with each other. For example, other embodiments may be used when a person skilled in the art reviews the above description. The abstract is provided to enable readers to quickly learn the technical disclosures disclosed in accordance with 37 C.F.R, §1.72 (b). The abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, several features can be grouped together to simplify the disclosure. This should not be interpreted to mean that an unclaimed disclosed feature is essential to all claims. Rather, the subject matter may fall within the scope of all features of a specific disclosed embodiment. Accordingly, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment, and such embodiments may be combined with each other in various combinations or permutations. The scope of the invention should be defined with reference to the appended claims, along with the full scope of equivalents of the claims.

Claims (15)

It is adapted to receive an audio / video jack plug of another device and has an electrical contact for connecting to a conducting terminal of the audio / video jack plug. Jack connector (audio / video jack connector);
A detection for enabling electrical communication with the audio / video jack connector and for determining a resistance corresponding to a resistive load of the other device at a connection terminal of the audio / video jack plug Detection circuit; And
A processor communicatively coupled to the detection circuitry and adapted to identify the function of the other device according to the determined resistance
Including;
And an operation is configured by the processor based on the identified function. The method of claim 1,
The detection circuit is adapted to detect a change in the determined resistance,
And when the processor detects a change in the determined resistance, changes the operation of the device according to the change in the resistance. The method according to claim 1 or 2,
The apparatus further comprises a control logic circuit in electrical communication with the detection circuit and the processor,
The control logic circuit is configured to generate an interrupt to the processor when detecting a change in the determined resistance,
And the processor is configured to receive a value representing the determined resistance in association with the interrupt and initiate an identified operation according to the received value. 4. The method according to any one of claims 1 to 3,
The apparatus further comprises a sense circuit, in electrical communication with the control logic circuit, configured to detect the presence of the audio / video jack plug,
The detection circuit is configured to detect a change in resistance at the connection terminal while the audio / video jack plug is kept connected by the detection circuit.
And the processor is configured to initiate a second operation of the device in accordance with the detected change in resistance. The method according to any one of claims 1 to 4,
The audio / video jack connector includes a first electrical contact for connecting to a first connection terminal of the audio / video jack plug and a second electrical contact for connecting to a second connection terminal of the audio / video jack plug; ,
And the processor is configured to identify a function of the other device from a resistance determined at the first connection terminal and the second connection terminal. The method according to any one of claims 1 to 5,
The audio / video jack connector includes a plurality of electrical contacts for connecting to a plurality of connection terminals of the audio / video jack plug,
And the processor is configured to identify by the resistance determined at the connection terminal whether the other device comprises at least one of a headset, a video monitor or a microphone. A first device having an audio / video jack plug having one or more connection terminals; And
A second device having an audio / video jack connector adapted to receive an audio / video jack plug of the first device
Including;
The second device,
A resistor capable of electrical communication with the audio / video jack connector, the resistance being measurable at the connection terminal, the resistance including a resistive load at the connection terminal of the first device; Detection circuit; And
And a processor capable of telecommunications communication with the detection circuitry to determine the function of the other device according to the determined resistance and to set the operation of the second device according to the determined function. . The method of claim 7, wherein
The detection circuit is configured to detect a change in the determined resistance,
The processor is configured to, when detecting a change in the determined resistance, change the operation of the second device according to the detected change in resistance. The method according to claim 7 or 8,
The audio / video jack plug includes a plurality of connection terminals and a ground terminal,
And the processor is configured to identify by the resistance determined at the connection terminal whether the first device comprises at least one of a headset, a video monitor or a microphone. Detecting whether an audio / video jack plug of the first device is inserted into an audio / video jack connector of the second device;
Using the second device to determine a resistance at the one or more connection terminals of the audio / video jack plug, the resistance including a resistive load of the first device measurable at the connection terminal;
Identifying a function that can be performed by the first device using the second device according to a resistance at the one or more connection terminals; And
Configuring the second device according to a function that may be performed by the identified first device
Method comprising a. The method of claim 10,
Detecting a change in the determined resistance using the second device, and determining that the change has occurred while the audio / video jack plug is inserted; And
Initiating operation of the second device in accordance with the detected change in resistance. The method according to claim 10 or 11, wherein
Identifying the at least one function executable by the first device according to the resistance of the connection terminal comprises identifying by the second device that the first device has a headset,
Initiating operation of the second device may include at least one of a stop, play, fast forward, pause, and rewind operation of the second device. And initiating. The method according to any one of claims 10 to 12,
Determining the resistance of the one or more connection terminals of the audio / video jack plug includes determining the resistance of the plurality of connection terminals of the audio / video jack plug,
Identifying the function executable by the first device includes identifying the function executable by the first device according to the resistance of the first connection terminal,
The method comprises:
Detecting a change in the determined resistance at the second connection terminal using the second device; And
Initiating operation of the second device in accordance with a change in the detected resistance at the second connection terminal. 14. The method according to any one of claims 10 to 13,
Identifying the function that the first device can perform may include identifying by the second device according to the determined resistive load that the first device includes at least one of a headset, a microphone, and a video display. And comprising a step. Means for detecting whether an audio / video jack plug of a first device is inserted into an audio / video jack connector of a second device;
Means for determining, using the second device, a resistance at the one or more connection terminals of the audio / video jack plug, the resistance including a resistive load of the first device measurable at the connection terminal;
Means for identifying using the second device a function that may be performed by the first device according to a resistance at the one or more connection terminals; And
Means for setting the second device according to the identified function that may be performed by the first device
Apparatus comprising a.

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