An external sound card with channel switching function

Abstract

This utility model relates to an external sound card with a channel switching function. The main control unit is used to process audio signals of each channel. The encoding and decoding unit is used for digital-to-analog conversion of audio signals of each channel and analog-to-digital conversion of voice signals received by the microphone. The headphone amplification unit is used to provide sound driving signals for the speakers of each channel of the multi-channel headphones. The channel switching circuit is used to realize the switching of audio signals between the front channel and the bass / center channel in 7.1 channel mode, so that when the 7.1 channel headphones play stereo music, the bass part of the music is enhanced by the bass speaker and the center speaker, giving the listener a better listening experience.

Description

Technical Field

[0001] This utility model relates to the field of external sound card technology, specifically to an external sound card with channel switching function. Background Technology

[0002] An external sound card (USB sound card) is an external audio processing device that connects to a computer or mobile device via a USB interface. It is primarily used to improve sound quality and is typically used in professional recording and real-time audio processing. Unlike motherboard-integrated or PCI / ISA-interface built-in sound cards, its external design avoids electromagnetic interference and supports plug-and-play functionality across multiple platforms.

[0003] 7.1 channel external sound cards are typically used in conjunction with 7.1 channel headphones to provide multi-channel surround sound, support 7.1 channel output, and offer more accurate sound field positioning and an immersive listening experience. They are particularly suitable for FPS games and cinematic audio-visual entertainment. They provide professional-grade sound quality processing, use independent DAC and ADC chips, support 24bit / 192kHz high-resolution recording, and typically have a signal-to-noise ratio greater than 90dB. The purity of the sound quality far exceeds that of onboard sound cards, which is why they are widely loved.

[0004] Typically, when using a 7.1-channel external sound card and 7.1-channel headphones, the audio source device needs to provide a 7.1-channel audio source to create a stereo and immersive sound effect. If, when using a 7.1-channel external sound card and 7.1-channel headphones, the audio source device can only provide a stereo sound source, and since the stereo sound source can only drive the front speakers, only the front speakers in the 7.1-channel headphones will work, while the other speakers will not produce sound. Furthermore, the front speakers are not sensitive to low-frequency signals in music, resulting in a lack of bass in the music and affecting the listener's auditory experience. Utility Model Content

[0005] In view of this, it is necessary to provide an external sound card with channel switching function that can transmit stereo music to the bass / center speaker.

[0006] An external sound card with channel switching function is connected to an audio source device and a 7.1-channel headphone via a USB interface and a multi-channel headphone jack, respectively. The external sound card includes a main control unit, a codec unit, and a headphone amplifier unit connected in sequence.

[0007] The main control unit is connected to the audio source device through the USB interface. The main control unit is used to process the audio signals of each channel, change, modify or optimize the sound characteristics to meet the listener's preferences or the requirements of a specific scenario.

[0008] The main control unit includes a channel switching module, which is used to switch between the front channel and the bass / center channel in 7.1 channel mode. When listening to stereo music with multi-channel headphones, the bass / center speaker can obtain the sound signal from the front channel, increasing the bass effect of the sound signal.

[0009] The input terminal of the codec unit is connected to the main control unit, and the output terminal of the codec unit is connected to the headphone amplifier unit. The codec unit is used to convert the audio signals of each channel from digital signals to analog signals, and at the same time convert the received voice signals into digital signals.

[0010] The input terminal of the headphone amplifier unit is connected to the codec unit. The headphone amplifier unit includes a multi-channel headphone interface and is used to provide sound drive signals to the headphone speaker.

[0011] Preferably, the external sound card further includes a closed housing, the upper surface of which is provided with a button group, a volume knob and a status indicator light. The button group includes a bass boost button, a headphone switch button, a headphone mute button, a microphone mute button and a channel switch button. The headphone switch button is used to change the audio output port, so that the sound signal switches between a multi-channel headphone interface and a stereo headphone interface. The channel switch button is connected to the channel switch module and is used to control the switching of the sound signal between the bass / center channel and the front channel in 7.1 channel mode.

[0012] Preferably, a PCB circuit board is provided inside the enclosed housing, and the main control unit, the encoding / decoding unit and the headphone amplifier unit are disposed on the PCB circuit board. The headphone amplifier unit includes a preamplifier unit, a rear amplifier unit, a side amplifier unit, a bass / center amplifier unit and a stereo headphone amplifier unit.

[0013] The preamplifier unit, the rear amplifier unit, the side amplifier unit, and the bass / center amplifier unit are respectively provided with a front channel interface, a rear channel interface, a side channel interface, and a bass / center channel interface for corresponding connection of multi-channel headphones; the stereo headphone amplifier unit is provided with a stereo headphone interface for connecting stereo headphones.

[0014] Preferably, the channel switching module includes a control module and a flash memory module. The channel switching key is connected to the control module. The control module is used to receive the key press information of the channel switching key and transmit the sound data stored in the flash memory module to the corresponding channel interface.

[0015] Preferably, the DP and DM pins of the main control unit are connected to the USB interface to receive audio signals from the audio source device; the HDA-SYNC, HDA-BCLK, HDA-SDOUT, and HDA-SDIN pins of the main control unit are connected to the codec unit to realize data transmission and clock synchronization between the main control unit and the codec unit.

[0016] Preferably, the main control unit is connected to the bass boost button, the headphone switch button, the headphone mute button, the microphone mute button, the channel switch button, and the volume knob via multiple XGPIO pins to read the status of each button and knob and implement the corresponding control functions.

[0017] Preferably, the FR / HP-R and FR / HP-L pins of the codec unit are connected to the preamplifier unit, the SURR-R and SURR-L pins of the codec unit are connected to the postamplifier unit, the SSOUTR and SSOUTL pins of the codec unit are connected to the sideamplifier unit, the LEF and CENTER pins of the codec unit are connected to the bass / center amplifier unit, and the MIC1-R and MIC1-L pins of the codec unit are connected to the microphone interface.

[0018] The output of the preamplifier unit is connected to the front channel interface and the stereo headphone amplifier unit.

[0019] In the aforementioned external sound card with channel switching function, the main control unit processes the audio signals of each channel, the encoding / decoding unit performs digital-to-analog conversion of the audio signals of each channel and analog-to-digital conversion of the voice signals received by the microphone, the headphone amplification unit provides sound drive signals to the speakers of each channel of the multi-channel headphones, and the channel switching module in the main control unit switches the audio signals between the front channel and the bass / center channel in 7.1 channel mode. This allows the 7.1 channel headphones to play stereo music by emitting sound through the bass and center speakers, enhancing the bass part of the music and providing the listener with a better listening experience. This invention has a simple device structure, is easy to implement, has low cost, and is easy to promote. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of an external sound card with channel switching function according to an embodiment of the present invention.

[0021] Figure 2 This is a structural block diagram of an external sound card with channel switching function according to an embodiment of the present invention.

[0022] Figure 3This is a circuit diagram of the main control unit of an external sound card with channel switching function according to an embodiment of the present invention.

[0023] Figure 4 This is a circuit diagram of the button group of an external sound card with channel switching function according to an embodiment of this utility model.

[0024] Figure 5 This is a circuit diagram of the encoding / decoding unit of an external sound card with channel switching function according to an embodiment of the present invention.

[0025] Figure 6 This is a circuit diagram of the preamplifier unit of an external sound card with channel switching function according to an embodiment of the present invention.

[0026] Figure 7 This is a circuit diagram of the bass / center amplifier unit of an external sound card with channel switching function according to an embodiment of the present invention. Detailed Implementation

[0027] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings.

[0028] Please see Figure 1 and Figure 2 This paper illustrates an external sound card 100 with channel switching functionality, which connects to an audio source device and a 7.1-channel headphone jack via a USB interface and a multi-channel headphone jack, respectively. The external sound card includes a main control unit 30, an encoding / decoding unit 40, and a headphone amplifier unit connected in sequence.

[0029] The main control unit 30 is connected to the audio source device through the USB interface. The main control unit 30 is used to process the audio signals of each channel, change, modify or optimize the sound characteristics to meet the listener's preferences or the requirements of a specific scenario.

[0030] The main control unit 30 includes a channel switching module 31, which is used to switch between the front channel and the bass / center channel in the 7.1 channel mode. When listening to stereo music with multi-channel headphones, the bass / center speaker can obtain the sound signal from the front channel, thereby increasing the bass effect of the sound signal.

[0031] The input terminal of the encoding / decoding unit 40 is connected to the main control unit 30, and the output terminal of the encoding / decoding unit 40 is connected to the headphone amplifier unit. The encoding / decoding unit 40 converts the audio signals of each channel from digital signals to analog signals, and at the same time converts the received voice signals into digital signals.

[0032] The input terminal of the headphone amplifier unit is connected to the codec unit 40. The headphone amplifier unit includes a multi-channel headphone interface and is used to provide sound drive signals to the headphone speaker.

[0033] Specifically, the USB interface is used to connect the external sound card and the audio source device, providing the external sound card with a sound source and power supply.

[0034] Preferably, the external sound card further includes a closed housing 10. The upper surface of the closed housing 10 is provided with a button group, a volume knob 16, and a status indicator light. The button group includes a bass boost button 11, a headphone switch button 12, a headphone mute button 13, a microphone mute button 14, and a channel switch button 15. The headphone switch button 12 is used to change the audio output port, so that the sound signal switches between the multi-channel headphone interface and the stereo headphone interface 26. The channel switch button 15 is connected to the channel switching circuit 60 and is used to control the switching of the sound signal between the bass / center channel and the front channel in 7.1 channel mode.

[0035] Specifically, the bass boost button 11 is used to boost the low-frequency part of the audio signal in 7.1 channel mode; the headphone mute button 13 is used to control the opening and closing of the headphone audio output; and the microphone mute button 14 is used to control the opening and closing of the microphone input.

[0036] The volume knob 16 is used to control the volume of the output sound signal; the status indicator light is used to indicate the working status of the external sound card. When the USB interface is connected to the audio source device, the external sound card is powered on and started, and the status indicator light lights up.

[0037] Preferably, the enclosed housing 10 is provided with a PCB circuit board, and the main control unit 30, the encoding and decoding unit 40, the headphone amplifier unit and the channel switching circuit 60 are disposed on the PCB circuit board. The headphone amplifier unit includes a preamplifier unit 51, a rear amplifier unit 52, a side amplifier unit 53, a bass / center amplifier unit 54 and a stereo headphone amplifier unit 55.

[0038] The preamplifier unit 51, the rear amplifier unit 52, the side amplifier unit 53, and the bass / center amplifier unit 54 are respectively provided with a front channel interface 21, a rear channel interface 22, a side channel interface 23, and a bass / center channel interface 24 for corresponding connection of multi-channel headphones; the stereo headphone amplifier unit 55 is provided with a stereo headphone interface 26 for connecting stereo headphones.

[0039] Specifically, the PCB circuit board is also provided with a microphone interface 25, which is used to connect the microphone of a multi-channel headset to collect the voice signal input from the microphone.

[0040] The front channel interface 21, the rear channel interface 22, the side channel interface 23, the bass / center channel interface 24, the microphone interface 25, and the stereo headphone interface 26 are disposed on the side wall of the enclosed housing 10.

[0041] The headphone switching button 12 is used to switch the sound signal between the multi-channel headphone interface (front channel interface 21, rear channel interface 22, side channel interface 23, bass / center channel interface 24, etc.) and the stereo headphone interface 26, so that the external sound card can be used with 7.1 channel headphones or 3.5mm stereo headphones.

[0042] Preferably, the channel switching module 31 includes a control module and a flash memory module. The channel switching key 15 is connected to the control module. The control module is used to receive the key information of the channel switching key 15 and transmit the sound data stored in the flash memory module to the corresponding channel interface.

[0043] Specifically, when the external sound card is powered on, it defaults to normal playback mode, with the audio signal of the front channel being transmitted to the front channel interface 21 and the audio signal of the bass / center channel being transmitted to the bass / center channel interface 24.

[0044] When the channel switching key 15 is pressed, the control module receives the key information from the channel switching key 15 and transmits the audio signal of the front channel to the bass / center channel interface 24 and the audio signal of the bass / center channel to the front channel interface 21. This realizes the cross-switching of the audio signals of the front channel interface 21 and the bass / center channel interface 24, so that the stereo signal is played in the bass / center channel interface 24, thereby increasing the low-frequency components in the stereo signal and enhancing its bass effect.

[0045] Specifically, please refer to Figure 4 In this embodiment, the channel switching key 15 is electrically connected to the XGPIO-12 pin of the main control unit 30, and the main control unit 30 collects the status information of the channel switching key 15 through the XGPIO pin.

[0046] Preferably, please refer to Figure 3The DP and DM pins of the main control unit 30 are connected to the USB interface to receive audio signals from the audio source device; the HDA-SYNC, HDA-BCLK, HDA-SDOUT, and HDA-SDIN pins of the main control unit 30 are connected to the codec unit 40 to realize data transmission and clock synchronization between the main control unit 30 and the codec unit 40.

[0047] Specifically, the DP and DM pins of the main control unit 30 are used to receive audio signals emitted by the audio source device. The DP and DM pins are a pair of differential signal lines used for data transmission in the USB interface, transmitting data signals through changes in voltage difference. The DP and DM lines work together to form a differential signal pair, which can effectively resist electromagnetic interference and improve the reliability of data transmission.

[0048] Specifically, the HDA-SYNC and HDA-BCLK pins of the main control unit 30 are used to send a synchronization clock signal to the codec unit 40, ensuring that the timestamps of the codec unit 40 and the main control unit 30 are consistent. The HDA-SDOUT and HDA-SDIN pins of the main control unit 30 are used to complete data transmission with the codec unit 40, and the transmitted data includes audio data for each channel and voice signals received through the microphone.

[0049] Specifically, in this embodiment, the main control unit 30 is preferably a CM6212 chip. The CM6212 chip is a USB 2.0 high-speed audio processor chip that provides standard HDA, I2S TDM, and S / PDIF digital audio interfaces; it has a maximum output of 12 channels (8 TDM channels + 2 I2S channels + 2 S / PDIF channels) and a maximum input of 12 channels (8 TDM channels + 2 I2S channels + 2 S / PDIF channels); it supports I2C, SPI, and GPIO communication with external devices; it has a built-in MCU, integrating an 8051 microcontroller and 512KB flash memory, and supports code changes for USB topology or communication with external devices.

[0050] Preferably, the main control unit 30 is connected to the bass boost button 11, the headphone switch button 12, the headphone mute button 13, the microphone mute button 14, the channel switch button 15, and the volume knob 16 through multiple XGPIO pins, respectively, to read the state of each button and knob and realize the corresponding control functions.

[0051] Preferably, please refer to Figure 5 , Figure 6 and Figure 7The FR / HP-R and FR / HP-L pins of the codec unit 40 are connected to the preamplifier unit 51, the SURR-R and SURR-L pins of the codec unit 40 are connected to the postamplifier unit 52, the SSOUTR and SSOUTL pins of the codec unit 40 are connected to the side amplifier unit 53, the LEF and CENTER pins of the codec unit 40 are connected to the bass / center amplifier unit 54, and the MIC1-R and MIC1-L pins of the codec unit 40 are connected to the microphone interface 25.

[0052] The output of the preamplifier unit 51 is connected to the front channel interface 21 and the stereo headphone amplifier unit 55.

[0053] Specifically, in this embodiment, the codec unit 40 is preferably a CM9881 chip. The CM9881 chip is a 7.1-channel audio decoder used to decompose the digital signal transmitted from the front USB interface into front L / front R, side L / side R, rear L / rear R, center and bass, and convert the digital signal into an analog signal and output it to each power amplifier for amplification and output.

[0054] Specifically, in this embodiment, the preamplifier unit 51, the postamplifier unit 52, the side amplifier unit 53, the bass / center amplifier unit 54, and the stereo headphone amplifier unit 55 are preferably LS6132 chips. The LS6132 chip is a 33mW capacitor-free stereo headphone amplifier chip, using a QFN3x3-16L small package design, suitable for portable audio device applications that require saving PCB board space and cost. The chip has a total harmonic distortion plus noise of 0.03%, supports differential or single-ended input, and the gain selection supports four adjustable levels: -6dB, 0dB, 3dB, and 6dB. It has excellent low-frequency characteristics, high power supply rejection ratio, and low noise performance.

[0055] Specifically, under the control of the main control unit 30, the channel switching module 31 switches the audio signal transmitted to the front channel interface 21 to the bass / center channel interface 24. When listening to stereo music with 7.1 channel headphones, the audio signal is only transmitted to the front channel interface 21. At this time, only the front speaker produces sound. Since the front speaker is not sensitive to low-frequency signals in the audio signal, it affects the listener's hearing effect. After the channel switching circuit 60 completes the switching between the front channel and the bass / center channel, the audio signal is transmitted to the bass / center channel interface 24, where the bass speaker and center speaker produce sound, providing the listener with a better hearing effect.

[0056] In the aforementioned external sound card with channel switching function, the main control unit processes the audio signals of each channel, the encoding / decoding unit performs digital-to-analog conversion on the audio signals of each channel and analog-to-digital conversion on the voice signals received by the microphone, the headphone amplification unit provides sound drive signals to the speakers of each channel of the multi-channel headphones, and the channel switching circuit switches the audio signals between the front channel and the bass / center channel in 7.1 channel mode. This allows the 7.1 channel headphones to play stereo music by emitting sound through the bass and center speakers, enhancing the bass portion of the music and providing a better listening experience. This invention features a simple structure, is easy to implement, has low cost, and is readily available for widespread adoption.

[0057] It should be noted that this utility model is not limited to the above-described embodiments. Based on the inventive spirit of this utility model, those skilled in the art can make other changes, and these changes made based on the inventive spirit of this utility model should be included within the scope of protection claimed by this utility model.

Claims

1. An external sound card with channel switching function, connected to an audio source device and a 7.1 channel headphone jack via a USB interface and a multi-channel headphone jack respectively, characterized in that, It includes a main control unit, a codec unit, and an earphone amplifier unit connected in sequence, wherein, The main control unit is connected to the audio source device through the USB interface. The main control unit is used to process the audio signals of each channel, change, modify or optimize the sound characteristics to meet the listener's preferences or the requirements of a specific scenario. The main control unit includes a channel switching module, which is used to switch between the front channel and the bass / center channel in 7.1 channel mode. When listening to stereo music with multi-channel headphones, the bass / center speaker can obtain the sound signal from the front channel, increasing the bass effect of the sound signal. The input terminal of the codec unit is connected to the main control unit, and the output terminal of the codec unit is connected to the headphone amplifier unit. The codec unit is used to convert the audio signals of each channel from digital signals to analog signals, and at the same time convert the received voice signals into digital signals. The input terminal of the headphone amplifier unit is connected to the codec unit. The headphone amplifier unit includes a multi-channel headphone interface and is used to provide sound drive signals to the headphone speaker.

2. The external sound card with channel switching function as described in claim 1, characterized in that, The external sound card also includes a closed housing. The upper surface of the closed housing is provided with a button group, a volume knob, and a status indicator light. The button group includes a bass boost button, a headphone switch button, a headphone mute button, a microphone mute button, and a channel switch button. The headphone switch button is used to change the audio output port, allowing the sound signal to switch between a multi-channel headphone interface and a stereo headphone interface. The channel switch button is connected to the channel switch module and is used to control the switching of the sound signal between the bass / center channel and the front channel in 7.1 channel mode.

3. The external sound card with channel switching function as described in claim 2, characterized in that, The enclosed housing contains a PCB circuit board, on which the main control unit, the encoding / decoding unit, and the headphone amplifier unit are mounted. The headphone amplifier unit includes a preamplifier unit, a rear amplifier unit, a side amplifier unit, a bass / center amplifier unit, and a stereo headphone amplifier unit. The preamplifier unit, the rear amplifier unit, the side amplifier unit, and the bass / center amplifier unit are respectively provided with a front channel interface, a rear channel interface, a side channel interface, and a bass / center channel interface for corresponding connection of multi-channel headphones; the stereo headphone amplifier unit is provided with a stereo headphone interface for connecting stereo headphones.

4. The external sound card with channel switching function as described in claim 2, characterized in that, The channel switching module includes a control module and a flash memory module. The channel switching key is connected to the control module. The control module is used to receive the key press information of the channel switching key and transmit the sound data stored in the flash memory module to the corresponding channel interface.

5. The external sound card with channel switching function as described in claim 2, characterized in that, The DP and DM pins of the main control unit are connected to the USB interface to receive audio signals from the audio source device; the HDA-SYNC, HDA-BCLK, HDA-SDOUT, and HDA-SDIN pins of the main control unit are connected to the codec unit to realize data transmission and clock synchronization between the main control unit and the codec unit.

6. The external sound card with channel switching function as described in claim 5, characterized in that, The main control unit is connected to the bass boost button, the headphone switch button, the headphone mute button, the microphone mute button, the channel switch button, and the volume knob via multiple XGPIO pins to read the status of each button and knob and implement the corresponding control functions.

7. The external sound card with channel switching function as described in claim 3, characterized in that, The FR / HP-R and FR / HP-L pins of the codec unit are connected to the preamplifier unit, the SURR-R and SURR-L pins of the codec unit are connected to the postamplifier unit, the SSOUTR and SSOUTL pins of the codec unit are connected to the sideamplifier unit, the LEF and CENTER pins of the codec unit are connected to the bass / center amplifier unit, and the MIC1-R and MIC1-L pins of the codec unit are connected to the microphone interface. The output of the preamplifier unit is connected to the front channel interface and the stereo headphone amplifier unit.

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