Audio system
By combining a bias voltage module and a sound detection module, the microphone recording function of the audio system is controlled, which solves the problem of high power consumption in the audio system and extends the service life of the equipment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- EEASY TECH CO LTD
- Filing Date
- 2023-02-02
- Publication Date
- 2026-07-24
AI Technical Summary
Existing audio systems consume a lot of power when performing intelligent recording, keyword recognition, or voice command recognition, which leads to a shortened device lifespan.
The system employs a combination of a bias voltage module, a sound detection module, a microphone, a digital signal processor, and a sound recording module. The bias voltage module provides a bias voltage to the microphone, the sound detection module detects changes in the voltage signal, and the digital signal processor controls the on and off of the sound recording module, thereby reducing unnecessary power consumption.
By determining whether a sound signal is being input through the microphone, the system controls the opening and closing of the sound recording module, reducing the power consumption of the audio system and extending the lifespan of the device.
Smart Images
Figure CN116405830B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of sound detection technology, and more particularly to an audio system. Background Technology
[0002] To meet people's audio-visual needs in life and work, such as voice calls, video calls, listening to music, and watching videos, most terminals are equipped with audio systems, such as mobile phones, tablets, music players, and portable interactive toys.
[0003] Existing audio systems, when performing functions such as intelligent recording, keyword recognition, or voice command recognition, typically require receiving sound signals through microphones within the audio system. These signals are then continuously processed by components such as programmable gain amplifiers (PGA), analog-to-digital converters (ADC), filters, and digital signal processors (DSPs) to detect and recognize the sound signals. This process consumes a lot of power, which is not conducive to the long-term operation of such devices and shortens their lifespan.
[0004] Therefore, an audio system is needed to solve the aforementioned technical problems. Summary of the Invention
[0005] This invention provides an audio system to solve the problem of high power consumption.
[0006] In a first aspect, embodiments of the present invention provide an audio system, the system comprising:
[0007] The system includes a bias voltage module, a sound detection module, a microphone, a digital signal processor, and a sound recording module, among which:
[0008] The bias voltage module is electrically connected to the microphone and is used to provide bias voltage to the microphone;
[0009] The input terminal of the sound detection module is electrically connected to a predetermined position of the bias voltage module. The sound detection module is used to receive a first voltage signal from the bias voltage module and obtain a digital voltage signal based on the first voltage signal. The predetermined position is the position where the first voltage signal changes as the sound signal received by the microphone changes.
[0010] The input terminal of the digital signal processor is electrically connected to the output terminal of the sound detection module, and the output terminal of the digital signal processor is electrically connected to the sound recording module. The digital signal processor is used to receive the digital voltage signal and control the sound recording module to turn on or off based on the digital voltage signal.
[0011] The sound input module is also electrically connected to the microphone, and the sound input module is used to receive sound signals input from the microphone when it is turned on.
[0012] The technical solution of this invention includes a bias voltage module, a sound detection module, a microphone, a digital signal processor, and a sound recording module. The bias voltage module is electrically connected to the microphone and provides a bias voltage to it. The input terminal of the sound detection module is electrically connected to a predetermined position of the bias voltage module. The sound detection module receives a first voltage signal from the bias voltage module and obtains a digital voltage signal based on the first voltage signal. The predetermined position is where the first voltage signal changes as the sound signal received by the microphone changes. The input terminal of the digital signal processor is electrically connected to the output terminal of the sound detection module, and the output terminal of the digital signal processor is electrically connected to the sound recording module. The digital signal processor receives the digital voltage signal and controls the sound recording module to turn on or off based on the digital voltage signal. The sound recording module is also electrically connected to the microphone and receives the sound signal input from the microphone when it is on. This audio system can determine whether a sound signal is input from the microphone based on a second voltage from the sound detection module, thereby controlling the sound recording module to turn on or off, reducing the power consumption of the audio system. Attached Figure Description
[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0014] in:
[0015] Figure 1 This is a schematic diagram of the structure of an audio system in one embodiment;
[0016] Figure 2 This is a schematic diagram of the structure of an audio system in one embodiment. Detailed Implementation
[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0018] This invention provides an audio system that can be applied to situations where a sound signal is detected input to the microphone 3, thereby controlling the activation of the sound recording module 5. This audio system can be implemented using both software and hardware methods, such as... Figure 1 As shown, the audio system of this embodiment includes: a bias voltage module 1, a sound detection module 2, a microphone 3, a digital signal processor 4, and a sound recording module 5, wherein:
[0019] The bias voltage module 1 is electrically connected to the microphone 3 and is used to provide a bias voltage to the microphone 3. The input terminal of the sound detection module 2 is electrically connected to a predetermined position of the bias voltage module 1. The sound detection module 2 is used to receive a first voltage signal from the bias voltage module 1 and obtain a digital voltage signal based on the first voltage signal. The predetermined position is the position where the first voltage signal changes as the sound signal received by the microphone 3 changes. The input terminal of the digital signal processor 4 is electrically connected to the output terminal of the sound detection module 2. The output terminal of the digital signal processor 4 is electrically connected to the sound recording module 5. The digital signal processor 4 is used to receive the digital voltage signal and control the sound recording module 5 to turn on or off based on the digital voltage signal. The sound recording module 5 is also electrically connected to the microphone 3 and is used to receive the sound signal input from the microphone 3 when it is turned on.
[0020] Microphone 3 can receive sound signals and convert them into electrical signals, so that the sound signals are input into the audio system in the form of current signals.
[0021] The technical solution of this invention includes a bias voltage module 1, a sound detection module 2, a microphone 3, a digital signal processor 4, and a sound recording module 5. The bias voltage module 1 is electrically connected to the microphone 3 and provides a bias voltage to the microphone 3. The input terminal of the sound detection module 2 is electrically connected to a predetermined position of the bias voltage module 1. The sound detection module 2 receives a first voltage signal from the bias voltage module 1 and obtains a digital voltage signal based on the first voltage signal. The predetermined position is the position where the first voltage signal changes as the sound signal received by the microphone 3 changes. The input terminal of the digital signal processor 4 is electrically connected to the output terminal of the sound detection module 2, and the output terminal of the digital signal processor 4 is electrically connected to the sound recording module 5. The digital signal processor 4 is used to receive digital voltage signals and control the sound recording module 5 to turn on or off based on the digital voltage signals. The sound recording module 5 is also electrically connected to the microphone 3. The sound recording module 5 is used to receive the sound signal input by the microphone 3 when it is turned on. In the audio system of this embodiment, the second voltage of the sound detection module 2 can be used to determine whether the microphone 3 is inputting a sound signal, and then control the sound recording module 5 to turn on or off, so that the sound recording module 5 is turned on only when there is a sound signal, thereby reducing the power consumption of the audio system.
[0022] In another embodiment of the invention, the predetermined position is the position where the first voltage signal changes as the sound signal received by the microphone 3 changes, and is the position where the change is the greatest.
[0023] In another embodiment of the invention, such as Figure 2 As shown, the bias voltage module 1 includes an operational amplifier OP, a first PMOS transistor MP1, and a first resistor R1; the positive input terminal of the operational amplifier OP is electrically connected to one end of the first resistor R1, and the other end of the first resistor R1 is grounded; the inverting input terminal of the operational amplifier OP is connected to a reference voltage, and the inverting input terminal of the operational amplifier OP serves as the input terminal of the bias voltage module 1; the output terminal of the operational amplifier OP is electrically connected to the gate of the first PMOS transistor MP1, and the output terminal of the operational amplifier OP serves as a predetermined position of the bias voltage module 1; the drain of the first PMOS transistor MP1 is electrically connected to the microphone 3, and the drain of the first PMOS transistor MP1 serves as the output terminal of the bias voltage module 1; the source of the first PMOS transistor MP1 is connected to a high level.
[0024] In this embodiment, the bias voltage module 1 provides a bias voltage to the microphone 3, enabling the microphone 3 to function normally. The reference voltage in this embodiment refers to the low-noise reference voltage (…). Figure 2In V1), each audio system has a corresponding low-noise reference voltage. The low-noise reference voltage comes from a low-temperature coefficient bandgap reference power supply.
[0025] In this embodiment of the invention, the connection relationship between the various components included in the bias voltage module 1 is described to clarify the transmission process of the voltage signal in the bias voltage module 1.
[0026] It should be understood that Figure 2 In this configuration, OP stands for Operational Amplifier, and the first PMOS transistor MP1 is the output stage PMOS transistor. The bias voltage module 1 also includes a fourth resistor R4 and a first capacitor C1. The output terminal of the operational amplifier OP is connected to one end of the fourth resistor R4, and the other end of the fourth resistor R4 is connected to one end of the first capacitor C1. The other end of the first capacitor C1 is connected to the drain of the first PMOS transistor MP1. The fourth resistor R4 serves as a compensation resistor, and the first capacitor C1 serves as a compensation capacitor. Optionally, the bias voltage module 1 also includes a third resistor R3. One end of the third resistor R3 is connected to the drain of the first PMOS transistor MP1, and the other end of the third resistor R3 is connected to the positive input terminal of the operational amplifier OP.
[0027] In this embodiment of the invention, the output voltage of the bias voltage module 1 is equal to V4 = (1 + R3 / R1) * V1, where V1 is the low-noise reference voltage. When the bias voltage module 1 provides a bias voltage to the microphone 3, the microphone 3 can perform sound-to-electric conversion. When there is no sound signal input, the current signal flowing through the microphone 3 is the quiescent current I1 of the microphone 3. At this time, the current signal of the first PMOS transistor MP1 is equal to I4. 11 =I1+V4 / (R3+R1), where V4 / (R3+R1) refers to the current flowing through the third resistor R3 and the first resistor R1, which is also the fixed static current of the first PMOS transistor MP1.
[0028] When an audio signal enters microphone 3, microphone 3 performs sound-to-electrical conversion, generating a current signal I2. I2 is the dynamic current generated by the microphone 3 in response to the sound, and its magnitude is related to the sensitivity of microphone 3 and the sound pressure level. At this time, two currents flow through microphone 3: a static current I1 and a dynamic current I2. The current signal flowing through the first PMOS transistor MP1 at this time is: I... 11 =I1+V4 / (R3+R1)±I2.
[0029] In another embodiment of the invention, such as Figure 2As shown, the sound detection module 2 includes: a second PMOS transistor MP2, a current mirror module 8, a microphone static current compensation module 9, an analog-to-digital converter module 6, and a signal acquisition module 7, wherein: the gate of the second PMOS transistor MP2 is connected to the output terminal of the operational amplifier OP, and the gate of the second PMOS transistor MP2 serves as the input terminal of the sound detection module 2; the source of the second PMOS transistor MP2 is connected to a high level; the drain of the second PMOS transistor MP2 is connected to one end of the current mirror module 8 and to one end of the microphone static current compensation module 9; the other end of the microphone static current compensation module 9 is grounded; the other end of the current mirror module 8 is connected to the input terminal of the signal acquisition module 7 through the analog-to-digital converter module 6; the output terminal of the signal acquisition module 7 is connected to one end of the digital signal processor 4, and the output terminal of the signal acquisition module 7 serves as the output terminal of the sound detection module 2.
[0030] Specifically, the gate of the second PMOS transistor MP2 is electrically connected to the output of the operational amplifier OP and serves as the input of the sound detection module 2. The source of the second PMOS transistor MP2 is connected to a high level, and the drain of the second PMOS transistor MP2 is electrically connected to one end of the current mirror module 8 and one end of the microphone static current compensation module 9. The other end of the current mirror module 8 is electrically connected to the input of the signal acquisition module 7 through a module conversion module. The output of the signal acquisition module 7 is electrically connected to one end of the digital signal processor 4. The output of the signal acquisition module 7 serves as the output of the sound detection module 2. In this embodiment, the microphone static current compensation module 9 is used to compensate for the static current of the microphone 3. The microphone static current compensation module 9 can be an integrated circuit, wherein the current I3 of the microphone static current compensation module 9 is configurable and configured according to the microphone 3 from different manufacturers. The current mirror module 8 subtracts the current I3 of the microphone static current compensation module 9 from the current flowing through MP2 and uses the resulting current difference as the output current of the current mirror module 8. By sensing the voltage signal V2 at the output of the operational amplifier OP, V2 is processed to obtain a voltage signal V3 that can reflect the presence or absence of a sound signal. The voltage signal V3 is then processed by the analog-to-digital converter module 6 and the signal acquisition module 7 to obtain a digital voltage signal.
[0031] Optionally, the second PMOS transistor MP2 and the first PMOS transistor MP1 are set to have the same length and proportional width: W MP1 / W MP2=M. M is a positive integer, and W represents the width. In this embodiment of the invention, the width of the first PMOS transistor MP1 is much larger than the width of the second PMOS transistor MP2. The gates of the first PMOS transistor MP1 and the second PMOS transistor MP2 are connected to the same voltage signal V2, so the current relationship between the first PMOS transistor MP1 and the second PMOS transistor MP2 is: I MP2 =I MP1 / M.
[0032] In another embodiment of the invention, the current mirror module 8 includes a first NMOS transistor MN1 and a second NMOS transistor MN2; the gate of the first NMOS transistor MN1 is electrically connected to the gate of the second NMOS transistor MN2; the gate of the first NMOS transistor MN1 is also electrically connected to the drain of the second PMOS transistor MP2; the source of the first NMOS transistor MN1 is grounded, and the drain of the first NMOS transistor MN1 is electrically connected to the gate of the first NMOS transistor MN1; the source of the second NMOS transistor MN2 is grounded, and the drain of the second NMOS transistor MN2 is electrically connected to one end of the analog-to-digital conversion module 6.
[0033] In this embodiment of the invention, the current mirror module 8 includes two NMOS transistors, namely a first NMOS transistor MN1 and a second NMOS transistor MN2. The two transistors are connected as follows: the gate of the first NMOS transistor MN1 is connected to the gate of the second NMOS transistor MN2; the gate of the first NMOS transistor MN1 is also electrically connected to the drain of the second PMOS transistor MP2; the drain of the first NMOS transistor MN1 is electrically connected to the gate of the first NMOS transistor MN1; the source of the second NMOS transistor MN2 and the source of the first NMOS transistor MN1 are both grounded; and the drain of the second NMOS transistor MN2 is electrically connected to one end of the analog-to-digital conversion module 6.
[0034] Optionally, the sound detection module 2 also includes a fifth resistor, one end of which is connected to a high level, and the other end is connected to the drain of the second NMOS transistor MN2, for converting the current of the current mirror module 8 into a voltage signal, so as to transmit the voltage signal ( Figure 2 V3 in the above is used as the input signal of the analog-to-digital converter module 6.
[0035] Optionally, in this embodiment of the invention, the two NMOS transistors have the same length and width. The current I of the first NMOS transistor MN1 in the current mirror module 8... MN1 The current signal I of the second NMOS transistor MN2 MN2 The relationship is: I MN1 =I MN2 ,
[0036] Alternatively, the microphone 3, the second resistor R2, and the second capacitor C2 can be printed on a circuit board.
[0037] With microphone 3 operating normally, the currents of the first PMOS transistor MP1, the second PMOS transistor MP2, the first NMOS transistor MN1, and the second NMOS transistor MN2 are as follows: I MP2 =I MP1 / M=[I1+V4 / (R3+R1)±I2] / M
[0038] The current flowing through the first NMOS transistor MN1 is: I MN1 =I MP2 -I3=I MP2 -I1 / M
[0039] I MN1 =[V4 / (R3+R1)±I2] / M
[0040] Since the second NMOS transistor MN2 has the same dimensions as the first NMOS transistor MN1, the current signal flowing through the second NMOS transistor MN2 is:
[0041] I MN2 =[V4 / (R3+R1)±I2] / M
[0042] In this embodiment of the invention, the resistance value of the fifth resistor R5 is set to R5 = R1 * M.
[0043] Then V3 = Avcc - I MN2 *R5
[0044]
[0045] Simplifying the above formulas, we get V4 = (1 + R3 / R1) * V1, R5 = R1 * M
[0046]
[0047]
[0048] V3=Avcc-V1±I2*R1
[0049] In this embodiment of the invention, V1 is set to Avcc / 2, then the above formula is rearranged as follows:
[0050]
[0051] The voltage signal V3 is equal to the fluctuation of an AC signal at the DC bias point of 0.5*Avcc. The magnitude of the fluctuation of the AC signal is related to the sound intensity entering the microphone 3, but is not related to the value of V4. It is only related to the first resistor R1. Therefore, the fluctuation of the voltage signal V3 can be used to determine whether a sound signal has entered the microphone 3.
[0052] The voltage signal V3 is transmitted to the signal acquisition module 7 via the analog-to-digital converter module. After being sampled by the clock, the resulting digital signal V5 is sent to the digital signal processor 4. The clock frequency is 32kHz. When the digital signal processor 4 receives the digital signal V5 from the signal acquisition module 7, it will activate the sound recording module 5 and enter normal operation whenever there is an edge change, such as a transition from high level to low level or from low level to high level. The digital signal processor 4 then receives the audio signal transmitted by the sound recording module 5.
[0053] The digital signal processor 4 makes a judgment based on the audio signal. If the audio signal is a voice command or keyword, it will perform the relevant operation. If not, it will shut down the sound input module 5 and continue to wait for the digital voltage signal V5 transmitted by the sound receiving module.
[0054] When the digital signal processor 4 is recording, it receives the digital signal V5 sent by the signal acquisition module 7 and detects a change in the edge. It then starts the sound recording module 5 and enters the normal working state. The digital signal processor 4 receives the audio signal transmitted by the sound recording module 5 and stores it. After the recording is completed, it continues to wait for the digital voltage signal V5 transmitted by the register.
[0055] Optionally, the sound recording module 5 can operate in a low-power state when in standby mode so that the sound recording module 5 can be started quickly.
[0056] In another embodiment of the invention, the digital signal processor 4 refers to a DSP.
[0057] In another embodiment of the invention, the analog-to-digital conversion module 6 includes a Schmitt hysteresis inverter.
[0058] In another embodiment of the invention, the signal acquisition module 7 includes a register. Optionally, the register is a latch register DFF.
[0059] In another embodiment of the invention, the system further includes a second resistor R2; the drain of the first PMOS transistor MP1 is connected to the microphone 3 through the second resistor R2.
[0060] In this embodiment of the invention, the bias voltage module 1 provides a bias voltage to the microphone 3. The microphone 3 performs acoustic-to-electrical conversion, converting the sound signal into a current signal. The amplitude of the current signal is related to the sound intensity of the sound signal entering the microphone 3 and the sensitivity of the microphone 3. The current signal is then converted into a voltage by a second resistor to obtain the voltage to be processed, which is then received by the sound recording module 5.
[0061] In another embodiment of the invention, the system further includes a second capacitor C2; the sound recording module 5 is electrically connected to the microphone 3 through the second capacitor C2.
[0062] In this embodiment of the invention, after the DC voltage is filtered out by the second capacitor C2, the voltage signal V6 is obtained and sent to the sound recording module 5.
[0063] In another embodiment of the invention, the sound recording module 5 includes a programmable gain amplifier, an analog-to-digital converter submodule, and a filter. Optionally, the sound recording module 5 and the digital signal processor 4 can be integrated into the same chip.
[0064] In this embodiment of the invention, the programmable gain amplifier (PGA) in the sound recording module 5 first receives the voltage signal V6 (i.e., the audio signal), amplifies the voltage signal V6, inputs the amplified voltage signal into the analog-to-digital conversion submodule to obtain the digital voltage sub-signal, inputs the digital voltage sub-signal into the filter for filtering, and then sends the processed digital voltage sub-signal into the digital signal processor 4 for analysis and processing to complete the recording of the sound signal.
[0065] The above description discloses only preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.
Claims
1. An audio system, characterized in that, It includes a bias voltage module, a sound detection module, a microphone, a digital signal processor, and a sound recording module, among which: The bias voltage module is electrically connected to the microphone and is used to provide bias voltage to the microphone; The input terminal of the sound detection module is electrically connected to a predetermined position of the bias voltage module. The sound detection module is used to receive a first voltage signal from the bias voltage module and obtain a digital voltage signal based on the first voltage signal. The predetermined position is the position where the first voltage signal changes with the sound signal received by the microphone, and is the position where the change is the greatest. The input terminal of the digital signal processor is electrically connected to the output terminal of the sound detection module, and the output terminal of the digital signal processor is electrically connected to the sound recording module. The digital signal processor is used to receive the digital voltage signal and control the sound recording module to turn on or off based on the digital voltage signal. The sound input module is also electrically connected to the microphone, and the sound input module is used to receive the sound signal input from the microphone when it is turned on. The bias voltage module includes an operational amplifier, a first PMOS transistor, and a first resistor. The positive input terminal of the operational amplifier is connected to one end of the first resistor, and the other end of the first resistor is grounded. The inverting input terminal of the operational amplifier is connected to a reference voltage and serves as the input terminal of the bias voltage module. The output terminal of the operational amplifier is connected to the gate of the first PMOS transistor and serves as a predetermined position of the bias voltage module. The drain of the first PMOS transistor is electrically connected to a microphone and serves as the output terminal of the bias voltage module. The source of the first PMOS transistor is connected to a high level. The sound detection module includes: a second PMOS transistor, a current mirror module, a microphone quiescent current compensation module, an analog-to-digital converter module, and a signal acquisition module. The gate of the second PMOS transistor is connected to the output of the operational amplifier, serving as the input of the sound detection module. The source of the second PMOS transistor is connected to a high level. The drain of the second PMOS transistor is connected to one end of the current mirror module and another end of the microphone quiescent current compensation module. The other end of the microphone quiescent current compensation module is grounded. The other end of the current mirror module is connected to the input of the signal acquisition module via the analog-to-digital converter module. The output of the signal acquisition module is connected to one end of the digital signal processor, serving as the output of the sound detection module.
2. The system according to claim 1, characterized in that, The current mirror module includes a first NMOS transistor and a second NMOS transistor; The gate of the first NMOS transistor is connected to the gate of the second NMOS transistor; The gate of the first NMOS transistor is also connected to the drain of the second PMOS transistor; The source of the first NMOS transistor is grounded, and the drain of the first NMOS transistor is connected to the gate of the first NMOS transistor. The source of the second NMOS transistor is grounded, and the drain of the second NMOS transistor is connected to one end of the analog-to-digital converter module.
3. The system according to claim 1, characterized in that, The analog-to-digital conversion module includes a Schmitt hysteresis inverter.
4. The system according to claim 1, characterized in that, The signal acquisition module includes registers.
5. The system according to claim 1, characterized in that, The system also includes a second capacitor; The sound recording module is connected to the microphone via a second capacitor.
6. The system according to claim 1, characterized in that, The system also includes a second resistor; The drain of the first PMOS transistor is connected to the microphone via a second resistor.
7. The system according to claim 1, characterized in that, The audio recording module includes a programmable gain amplifier, an analog-to-digital converter submodule, and a filter.