CN116203868A - Multi-audio priority processing type digital power amplifier device and processing method thereof - Google Patents

Abstract

The invention discloses a multi-audio priority processing type digital power amplifier device and a processing method thereof, belonging to the technical field of vehicle audio processing devices, comprising: a power amplifier device body, the power amplifier device body is externally connected with a plurality of audio signal input ends, the An audio priority processor is provided in the body of the power amplifier device, and the audio priority processor uses the sound mixing function to process the audio signal, and according to the difference of the input audio signal, it is identified in the audio priority processor, and according to the set The priority order is judged, and the signal with high priority is transmitted to the lower level; it realizes automatic switching of multiple audio priorities, which is suitable for vehicles with multiple audio sources input. Improve the intelligence of the vehicle audio system. To solve the problem of insufficient power of the audio output host, the device converts two-channel stereo signals into multi-channel surround sound signals. To solve the audio defects caused by the environment in the car, the speakers in the car should be installed to optimize the sound field in the car.

Description

Multi-audio priority processing digital power amplifier device and processing method thereof

technical field

The invention relates to a multi-audio priority processing type digital power amplifier device and a processing method thereof, belonging to the technical field of vehicle audio processing devices.

Background technique

When there are multiple audio inputs in the vehicle: such as vehicle station announcer, microphone, car TV, car radio, etc., when the host is working at the same time, noise and mixing will occur, so that the driver and passengers cannot accurately receive accurate audio information. judge. The existing solution is to use physical buttons to switch manually, which cannot effectively realize the automatic switching of vehicle audio, and there are potential safety hazards for the driver during the operation. And the DSP power amplifier can only manage one or two audio signals through processing optimization and management of audio parameters.

At the same time, because in the car, the installation position of the speakers cannot be maintained on the same interface as the home audio system, and the pointing angles often vary. The sound reproduced by each speaker is very different in position and phase, and the integrity of the sound will also become fragmented. Consumers need to frequently operate physical buttons during use, which is less comfortable and convenient. Therefore, how to realize the priority processing of multiple audio, so that passengers can accurately judge the sound, and improve the intelligence of the vehicle audio system has become an urgent need at present.

Contents of the invention

In view of the deficiencies in the prior art, the purpose of the present invention is to provide a multi-audio priority processing digital power amplifier device and its processing method, which can realize automatic switching of various audio priorities, and is suitable for vehicles with multiple audio sources input. . Improve the intelligence of the vehicle audio system. Reduce vehicle physical buttons and corresponding control modules, reduce vehicle weight, save energy and reduce emissions.

The multi-audio priority processing type digital power amplifier device described in the present invention includes:

A power amplifier body, the exterior of the power amplifier body is connected to a plurality of audio signal input terminals, and an audio priority processor is arranged in the power amplifier body, and the audio priority processor uses a mixing function to process audio signals , according to the different input audio signals, it is identified in the audio priority processor, judged according to the set priority order, and the signal with high priority is passed to the lower level;

The outside of the audio priority processor is connected with a pre-matching circuit and an AD/DA conversion module in sequence, and the outside of the AD/DA conversion module is connected with a DSP audio processing module and a power amplification module, and the DSP audio processing module is connected with the AD\ The DA conversion module performs data interaction. After the AD/DA conversion module receives the differential signal processed by the pre-matching circuit, the AD/DA conversion module inputs the converted format of the differential signal into the DSP audio processing module. After the audio processing by the DSP audio processing module Then input it into the AD\DA conversion module to realize data interaction;

The AD/DA conversion module converts the digital signal into an analog signal through the internal digital-to-analog converter, and outputs it to the power amplifier module through the processing of the filter circuit. The external connection of the power amplifier module has a plurality of audio signal output terminals for Amplified output of audio signal.

Further, the audio priority processor is provided with multiple audio input interfaces, the audio signal is input into the audio priority processor through the connector, and is switched according to the audio priority processing rules set by the audio priority processor, and various audio When signals are input at the same time, the audio signal with higher priority will automatically turn off the audio channel with lower priority.

Further, the pre-matching circuit includes an input interface circuit, the input interface circuit is connected with a resistance adjustment circuit, and the resistance adjustment circuit adjusts the amplitude of the input signal through resistors of different resistance values, and the resistance adjustment circuit is also connected with a DC blocking capacitor and TVS tube.

Further, the AD/DA conversion module adopts a CODEC chip integrating ADC and DAC, with 4 built-in ADC inputs and 8 DAC outputs.

Further, the DSP audio processing module adopts sigma series chips, with built-in 48 digital audio inputs and 48 digital audio outputs.

Further, the power amplifying module includes multiple power amplifier input circuits, and multiple speakers are connected to the output ends of the power amplifier input circuits.

Further, the body of the power amplifier device is also provided with a CAN communication module, and the CAN communication module is connected with a CAN bus and an MCU storage module.

Further, the body of the power amplifier device is also provided with a power management module, and the power management module is connected to the audio processing module and the CAN communication module for power supply.

The audio processing method of the multi-audio priority processing type digital power amplifier device described in the present invention comprises the following steps:

S1: Different audio source signals are input to the audio priority processor through the audio signal input terminal. The audio priority processor uses the mixing function to process the audio signal. According to the different input audio signals, it is identified in the audio priority processor. Judgment is made according to the set priority order, and the signal with high priority is passed to the lower level;

S2: The recognized audio signal is transmitted to the DSP power amplifier module in the audio priority processor for digital processing. The processing method is to perform corresponding step-down processing on the signal and input it to the pre-matching circuit for adjustment to adjust the amplitude of the input signal. , the processed signal is passed to the AD\DA conversion module;

S3: After the AD/DA conversion module receives the pre-processed differential signal, the AD-converted signal into I2S format is input to the DSP audio processing module. After the audio processing by the DSP audio processing module, the EQ value and channel delay of the audio signal are adjusted. Time and phase, high and low pass processing on the audio, and the I2S signal is input to the AD\DA conversion module, and the digital signal is converted into an analog signal through the internal digital-to-analog converter, and the signal is processed by the filter circuit and output to the power amplifier module;

S4: DSP audio processing module to debug the sound field and sound effect in the car, and at the same time, self-start through the external EEPROM program, and debug with the tuning software;

S5: The power amplifier module amplifies the received audio and outputs it to the speaker for sound reproduction.

Further, in step S1, different sound sources are input into the audio priority processor through different channels, and the priority order set in the audio priority processor is decremented according to the label of the channel, when it is detected that the channel with higher priority has audio input , the audio signal is also used as a control signal to automatically cut off the channel with low priority.

Compared with the prior art, the present invention has the following beneficial effects:

The multi-audio priority processing type digital power amplifier device and the processing method thereof described in the present invention realize automatic switching of multiple audio priority levels, and are suitable for vehicles with multiple audio source inputs. Improve the intelligence of the vehicle audio system. Reduce vehicle physical buttons and corresponding control modules, reduce vehicle weight, save energy and reduce emissions. To solve the problem of insufficient power of the audio output host, the device converts two-channel stereo signals into multi-channel surround sound signals. To solve the audio defects caused by the environment in the car, the speakers in the car should be installed to optimize the sound field in the car.

This product has a variety of application scenarios, among which it can be applied to tourist buses. In the actual use process, signals such as radios and TVs are transmitted to the processor, and output to the speakers in the car for playback. When the tour guide uses a wireless microphone to explain Tour information, during the use of the microphone, the microphone receives the voice information of the tour guide and transmits it to the processor. The processor automatically cuts off the TV and radio signals, and only plays the tour guide's explanation voice. In the process of explaining, if encountering site information, it will automatically cut off the signal of the wireless microphone and only play the station information.

Description of drawings

Fig. 1 is the structural diagram of multi-audio priority processing type digital power amplifier device of the present invention;

Fig. 2 is the connection schematic diagram of multi-audio priority processing type digital power amplifier device of the present invention;

3 is a circuit diagram of an audio priority processor in a multi-audio priority processing type digital power amplifier device of the present invention;

Fig. 4 is the circuit diagram of the pre-matching circuit in the multi-audio priority processing type digital power amplifier device of the present invention;

5 is a circuit diagram of an AD/DA conversion module in the multi-audio priority processing type digital power amplifier device of the present invention;

Fig. 6 is the circuit diagram of the DSP audio processing module in the multi-audio priority processing type digital power amplifier device of the present invention;

FIG. 7 is a circuit diagram of a power amplification module in a multi-audio priority processing digital power amplifier device according to the present invention.

Detailed ways

Below in conjunction with accompanying drawing and embodiment the present invention will be further described:

Example 1:

As shown in Figure 1-2, the multi-audio priority processing type digital power amplifier device described in the present invention includes a power amplifier device body, and a plurality of audio signal input terminals are connected to the outside of the power amplifier device body, and audio priority Level processor, the audio priority processor uses the audio mixing function to process the audio signal, according to the different input audio signals, it is identified in the audio priority processor, and the priority is determined according to the set priority order, and the priority The high signal is transmitted to the lower level; the outside of the audio priority processor is connected with a pre-matching circuit and an AD/DA conversion module in turn, and the outside of the AD/DA conversion module is connected with a DSP audio processing module and a power amplifier module, and the DSP audio processing module Perform data interaction with the AD\DA conversion module. After the AD/DA conversion module receives the differential signal processed by the pre-matching circuit, the AD\DA conversion module inputs the conversion format of the differential signal into the DSP audio processing module. Through the DSP audio processing module After audio processing, it is input to the AD/DA conversion module to realize data interaction; the AD/DA conversion module converts the digital signal into an analog signal through the internal digital-to-analog converter, and outputs it to the power amplifier module after processing by the filter circuit. The external connection of the amplifying module is provided with a plurality of audio signal output terminals for amplifying and outputting the audio signal.

In this embodiment, automatic switching of four audio priorities is realized, station announcement>microphone>video audio>radio. Identify in the level processor, judge according to the set priority order, and pass the signal with high priority to the lower level. Different audio sources are input to the priority controller through channel 1, channel 2, channel 3 and channel 4. The order of priority is in descending order of channels 1-4. When audio input is detected from a channel with a higher priority, the audio signal is used as a control signal to automatically cut off the channel with a lower priority. For example, when the processor recognizes the electrical signal transmitted by channel 1, if other channels have audio input, it will be automatically closed, so that channels 2-4 are in a disconnected state and no audio transmission is performed.

The recognized audio signal is transmitted to the DSP power amplifier module for digital processing. The processing method is to perform corresponding step-down processing on the signal and input it to the front-end configuration circuit for adjustment to adjust the amplitude of the input signal. Avoid the distortion of the signal input to the ADC beyond the input range of the ADC due to excessive signal, suppress pulse interference, etc., and pass the processed signal to the AD\DA conversion module.

After the AD/DA conversion module receives the pre-processed differential signal, the AD converted signal into I2S format is input to the DSP chip, and after the audio processing of the DSP chip, the EQ value, channel delay, and phase of the audio signal are adjusted, and the audio frequency is adjusted. Perform high and low-pass processing, and input the I2S signal to the AD\DA conversion module, convert the digital signal into an analog signal through the internal digital-to-analog converter, and then output the signal to the power amplifier module after being processed by the filter circuit.

The DSP audio processing module is used to debug the sound field and sound effects in the car, and at the same time, the program in the external EEPROM is self-started. Cooperate with tuning software for debugging. The power amplifier module amplifies the received audio and outputs it to the speaker for sound reproduction.

As shown in Figure 3, there are multiple audio input interfaces inside the audio priority processor, and audio signals are input to the audio priority processor through connectors, and are switched according to the audio priority processing rules set by the audio priority processor , When multiple audio signals are input at the same time, the high-level signal input by the high-priority signal is used as a control signal to cut off the low-priority signal. Make the audio signal with higher priority automatically turn off the audio channel with lower priority.

The specific working logic is: the multi-channel signals are processed in different ways after being input, and the wireless microphone signal passes through the wireless microphone receiver after the input controller to pick up the signal, and the picked up signal is processed by the filter. Filter processing, processing the background noise, etc., to obtain a pure audio signal. At this time, the audio signal is matched and adjusted by the module for secondary processing, and processed into a "small signal" that can be processed by the operational amplifier. The filtered signal is divided into two signals through operational amplification, and one is given to the CPU as a priority identification signal. One channel is reproduced as the audio source signal output by the speaker. Because the other signals are hard-wired, the steps of signal pickup are omitted, and the other processing is the same.

The audio signal given to the CPU is used as a trigger switch, and the corresponding program is run to control the opening and closing of the switching circuit, so as to realize priority processing.

As shown in Figure 4, the pre-matching circuit includes an input interface circuit, the input interface circuit is connected with a resistance adjustment circuit, the resistance adjustment circuit adjusts the amplitude of the input signal through resistors of different resistance values, and the resistance adjustment circuit is also connected with a DC blocking capacitor and TVS tubes. The pre-matching circuit receives the audio signal input by the priority processing module, and in order to match the input signal, the corresponding input interface circuit is used on the controller.

For audio signal signals, the amplitude of the input signal can be adjusted through resistors of different resistance values. To avoid the distortion of the signal input to the ADC beyond the input range of the ADC due to excessive signal, the resistor in the module can also adjust the size of the input impedance.

DC blocking capacitor in the circuit: avoid damage caused by DC component input to the ADC interface.

TVS tube is used to suppress pulse interference.

In-line electrolytic capacitor in the circuit: E-CAP2200UF/25V105℃ Lowest Impedance Function: The electrolytic capacitor plays the role of power filtering, decoupling, signal coupling, time constant setting, DC blocking, etc. in the intermediate frequency and low frequency circuits, and is used as a filter capacitor.

High-power inductance in the circuit: JC1770TY-330MT-G33.0uH±20%, function: inductance is a property of a closed circuit and a physical quantity. When the current passes through the coil, a magnetic field induction is formed in the coil, and the induced magnetic field will generate an induced current to resist the current passing through the coil. It is a circuit parameter that describes the induced electromotive force effect in this coil or in another coil due to the change of coil current

The function of TVS diode in the circuit: TVS is a high-efficiency protection device in the form of a diode. When the two poles of the TVS diode are impacted by the reverse transient high energy, the high impedance between the two poles will be changed to low impedance, and the surge power of up to several thousand watts will be absorbed, so that the voltage between the two poles will be clamped at a predetermined value, effectively protecting Precise components in electronic circuits are protected from damage by various surge pulses.

MOS tube in the circuit: PMOS-FET-RM60P60HDV-TO-263-2L Function: Reverse protection circuit, without using diodes, the voltage drop is smaller and the power dissipation is less. When the circuit is powered on normally, GATE is connected to the 0 potential far lower than the D terminal, and the PMOS is fully turned on. When the power supply is reversed, the potential of GATE is much higher than that of S terminal, and PMOS is completely cut off.

As shown in Figure 5, the AD/DA conversion module uses a CODEC chip integrating ADC and DAC, with 4 built-in ADC inputs and 8 DAC outputs. This module uses a CODEC chip with high performance and single-chip integrated ADC and DAC from ADI. Built-in 4-channel ADC input, 8-channel DAC output, using ADI's multi-bit Σ-Δ patented architecture. It has a Serial Peripheral Interface (SPI) through which the microcontroller can adjust volume and many other parameters.

After the module receives the pre-processed signal, the AD converted signal into I2S format is input to the DSP chip. After DSP audio processing, the I2S signal is input to the module, and the digital signal is converted by the internal digital-to-analog converter. Converted into an analog signal, the signal is then processed by a filter circuit and output to the power amplifier chip.

As shown in Figure 6, the DSP audio processing module adopts sigma series chips, with built-in 48 digital audio inputs and 48 digital audio outputs. The module uses the ADAU1452 chip in the sigma series of ADI Company. It has built-in 48 digital audio inputs and 48 digital audio outputs. There are various processing modules, such as: FIR, IIR, FFT accelerator, etc., which are generally used in car audio processing. , can be used to debug the sound field and sound effects in the car, and can expand some simple chime sound playback and other functions. In the absence of a single-chip microcomputer, it can be self-started through the program in the external EEPROM. Cooperating with ADI's SIGMA tuning software allows designers to debug quickly and conveniently.

As shown in FIG. 7 , the power amplification module includes multiple power amplifier input circuits, and multiple speakers are connected to the output ends of the power amplifier input circuits. The input of the power amplifier is Single-Ended, so the analog signal output by the DAC uses the recommended filter circuit for single-ended output, and the periphery of the power amplifier IC uses the hardware settings recommended by the chip for processing. Specify the definition of the power amplifier output and connect to the corresponding speaker.

A CAN communication module is also arranged in the power amplifier body, and the CAN communication module is connected with a CAN bus and an MCU storage module. The function of the CAN signal is to communicate with each host to call the program of the MCU, such as: 1 calling different music styles, used for adjusting the volume, etc.

The body of the power amplifier device is also provided with a power management module, and the power management module is connected to the audio processing module and the CAN communication module for power supply.

Example 2:

The audio processing method of the multi-audio priority processing type digital power amplifier device described in the present invention comprises the following steps:

S1: Different audio source signals are input to the audio priority processor through the audio signal input terminal. The audio priority processor uses the mixing function to process the audio signal. According to the different input audio signals, it is identified in the audio priority processor. Judgment is made according to the set priority order, and the signal with high priority is passed to the lower level;

S2: The recognized audio signal is transmitted to the DSP power amplifier module in the audio priority processor for digital processing. The processing method is to perform corresponding step-down processing on the signal and input it to the pre-matching circuit for adjustment to adjust the amplitude of the input signal. , the processed signal is passed to the AD\DA conversion module;

S3: After the AD/DA conversion module receives the pre-processed differential signal, the AD-converted signal into I2S format is input to the DSP audio processing module. After the audio processing by the DSP audio processing module, the EQ value and channel delay of the audio signal are adjusted. Time and phase, high and low pass processing on the audio, and the I2S signal is input to the AD\DA conversion module, and the digital signal is converted into an analog signal through the internal digital-to-analog converter, and the signal is processed by the filter circuit and output to the power amplifier module;

S4: DSP audio processing module to debug the sound field and sound effect in the car, and at the same time, self-start through the external EEPROM program, and debug with the tuning software;

S5: The power amplifier module amplifies the received audio and outputs it to the speaker for sound reproduction.

In step S1, different audio sources are input into the audio priority processor through different channels, and the priority order set in the audio priority processor is decremented according to the label of the channel. When it is detected that the channel with higher priority has audio input, the audio signal At the same time, as a control signal, the channel with low priority is automatically cut off.

This product is applied to the tourist bus. In the actual use process, the radio, TV and other signals are transmitted to the processor, and output to the speaker in the car for playback. When the tour guide uses a wireless microphone to explain the tour information, the microphone is used. , the voice information of the tour guide is received by the microphone and transmitted to the processor. The processor automatically cuts off the TV and radio signals, and only plays the tour guide's explanation voice. In the process of explaining, if encountering site information, it will automatically cut off the signal of the wireless microphone and only play the station information.

Using the multi-audio priority processing digital power amplifier device and its processing method according to the embodiments of the present invention described above in conjunction with the accompanying drawings, the automatic switching of various audio priorities is realized, which is suitable for vehicles with multiple audio sources input. Improve the intelligence of the vehicle audio system. Reduce vehicle physical buttons and corresponding control modules, reduce vehicle weight, save energy and reduce emissions. To solve the problem of insufficient power of the audio output host, the device converts two-channel stereo signals into multi-channel surround sound signals. To solve the audio defects caused by the environment in the car, the speakers in the car should be installed to optimize the sound field in the car. However, the present invention is not limited to the described embodiments, and changes, modifications, replacements and deformations to the embodiments without departing from the principle and spirit of the present invention still fall within the protection scope of the present invention.

Claims (10)

1. A multi-audio priority processing type digital power amplifier device, characterized in that: comprising: A power amplifier body, the exterior of the power amplifier body is connected to a plurality of audio signal input terminals, and an audio priority processor is arranged in the power amplifier body, and the audio priority processor uses a mixing function to process audio signals , according to the different input audio signals, it is identified in the audio priority processor, judged according to the set priority order, and the signal with high priority is passed to the lower level; The outside of the audio priority processor is connected with a pre-matching circuit and an AD/DA conversion module in sequence, and the outside of the AD/DA conversion module is connected with a DSP audio processing module and a power amplification module, and the DSP audio processing module is connected with the AD\ The DA conversion module performs data interaction. After the AD/DA conversion module receives the differential signal processed by the pre-matching circuit, the AD/DA conversion module inputs the converted format of the differential signal into the DSP audio processing module. After the audio processing by the DSP audio processing module Then input it into the AD\DA conversion module to realize data interaction; The AD/DA conversion module converts the digital signal into an analog signal through the internal digital-to-analog converter, and outputs it to the power amplifier module through the processing of the filter circuit. The external connection of the power amplifier module has a plurality of audio signal output terminals for Amplified output of audio signal. 2. The multi-audio priority processing type digital power amplifier device according to claim 1, characterized in that: the audio priority processor is provided with a plurality of audio input interfaces, and audio signals are input to the audio priority processing through connectors In the device, it switches according to the audio priority processing rules set by the audio priority processor. When multiple audio signals are input at the same time, the audio signal with a higher priority will automatically close the audio channel with a lower priority. 3. The multi-audio priority processing type digital power amplifier device according to claim 1, characterized in that: the pre-matching circuit includes an input interface circuit, the input interface circuit is connected with a resistance adjustment circuit, and the resistance adjustment circuit passes Resistors with different resistance values are used to adjust the amplitude of the input signal, and the resistance adjustment circuit is also connected with a DC blocking capacitor and a TVS tube. 4. The multi-audio priority processing type digital power amplifier device according to claim 1, characterized in that: the AD/DA conversion module adopts a CODEC chip integrating ADC and DAC, with 4 built-in ADC inputs and 8 DAC outputs . 5. The multi-audio priority processing digital power amplifier device according to claim 1, characterized in that: the DSP audio processing module adopts a sigma series chip, and has 48 digital audio inputs and 48 digital audio outputs built in. 6. The multi-audio priority processing type digital power amplifier device according to claim 1, characterized in that: said power amplification module includes a multi-channel power amplifier input circuit, and a plurality of speakers are connected to the output end of the power amplifier input circuit. 7. The multi-audio priority processing type digital power amplifier device according to claim 1, characterized in that: the power amplifier device body is also provided with a CAN communication module, and the CAN communication module is connected with a CAN bus and an MCU storage module . 8. The multi-audio priority processing digital power amplifier device according to claim 1, characterized in that: the power amplifier device body is also provided with a power management module, and the power management module is connected to the audio processing module and the CAN communication module power supply. 9. An audio processing method for a multi-audio priority processing digital power amplifier device, applied to the multi-audio priority processing digital power amplifier device according to any one of claims 1-8, characterized in that: the method includes the following step: S1: Different audio source signals are input to the audio priority processor through the audio signal input terminal. The audio priority processor uses the mixing function to process the audio signal. According to the different input audio signals, it is identified in the audio priority processor. Judgment is made according to the set priority order, and the signal with high priority is passed to the lower level; S2: The recognized audio signal is transmitted to the DSP power amplifier module in the audio priority processor for digital processing. The processing method is to perform corresponding step-down processing on the signal and input it to the pre-matching circuit for adjustment to adjust the amplitude of the input signal. , the processed signal is passed to the AD\DA conversion module; S3: After the AD/DA conversion module receives the pre-processed differential signal, the AD-converted signal into I2S format is input to the DSP audio processing module. After the audio processing by the DSP audio processing module, the EQ value and channel delay of the audio signal are adjusted. Time and phase, high and low pass processing on the audio, and the I2S signal is input to the AD\DA conversion module, and the digital signal is converted into an analog signal through the internal digital-to-analog converter, and the signal is processed by the filter circuit and output to the power amplifier module; S4: DSP audio processing module to debug the sound field and sound effect in the car, and at the same time, self-start through the external EEPROM program, and debug with the tuning software; S5: The power amplifier module amplifies the received audio and outputs it to the speaker for sound reproduction. 10. The audio processing method of the multi-audio priority processing type digital power amplifier device according to claim 9, characterized in that, in the step S1, different audio sources are input into the audio priority processor through different channels, and the audio priority The priority order set in the processor is decremented according to the channel number. When audio input is detected from a channel with a higher priority, the audio signal is used as a control signal to automatically cut off the channel with a lower priority.

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