Power supply control circuit, audio power amplifier and audio system

Abstract

The utility model relates to the technical field of electronic products, and provides a power supply control circuit, an audio power amplifier and an audio system. The power supply control circuit comprises a detection sub-circuit and a control sub-circuit. The detection sub-circuit is used for detecting whether the audio power amplifier receives an audio signal and outputting a high / low level signal to the control sub-circuit and the microprocessor according to a detection result; the control sub-circuit is used for controlling the power supply state of the power supply module to the microprocessor according to the high / low level signal; the microprocessor is configured to control the audio power amplifier to be switched between a power-down state and a working state according to the high / low level signal. The power supply control circuit controls the audio power amplifier to be switched between the power-down state and the working state through a mode of detecting the audio signal, so that the audio power amplifier can work normally, and the power supply control circuit can be used for controlling the audio power amplifier to be switched between the power-down state and the working state. And the problem that the existing audio power amplifier is relatively high in power consumption during standby playing is effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic products, and in particular to a power supply control circuit, an audio power amplifier and an audio system. Background Art

[0002] The audio power amplifier is mainly used to amplify the input audio signal, and then drive the passive acoustic components (such as speakers, headphones, etc.) to produce sound through the amplified audio signal.

[0003] In practical applications, the audio power amplifier is usually powered on and started up through CAN messages or ACC control lines. When the audio power amplifier is playing silently, it is necessary to ensure that the audio power amplifier is powered so that the audio power amplifier remains in a standby state so that the audio power amplifier can respond immediately when receiving an audio signal. However, this power supply design causes the audio power amplifier to be unable to enter a power-off dormant state. The audio power amplifier needs to consume a relatively large standby current in the standby state, and the power consumption during standby playback is relatively large. Utility Model Content

[0004] The utility model provides a power supply control circuit, an audio power amplifier and an audio system, which are used to solve the problem that the power supply design of the existing audio power amplifier is unreasonable, resulting in high power consumption of the audio power amplifier during standby playback.

[0005] In a first aspect, the utility model provides a power supply control circuit, comprising:

[0006] The detection subcircuit is used to detect whether the audio power amplifier receives the audio signal, and output high / low level signals to the control subcircuit and the microprocessor respectively according to the detection result;

[0007] A control subcircuit, used for controlling the power supply state of the power module to the microprocessor according to the high / low level signal;

[0008] Wherein, the microprocessor is configured to control the audio power amplifier to switch between a power-off state and a working state according to the high / low level signal.

[0009] According to a power supply control circuit provided by the utility model, the detection subcircuit includes a signal conversion circuit and a signal discrimination circuit;

[0010] The signal conversion circuit is used to convert the audio signal into a single-ended signal;

[0011] The signal discrimination circuit is used to identify the category of the single-ended signal and output the high / low level signal corresponding to the category.

[0012] According to a power supply control circuit provided by the utility model, the signal conversion circuit is configured with multiple paths;

[0013] The multiple signal conversion circuits are configured to process the multiple audio signals in a one-to-one correspondence, and the multiple signal conversion circuits are commonly connected to one signal identification circuit.

[0014] According to a power supply control circuit provided by the utility model, the signal conversion circuit includes an operational amplifier;

[0015] The non-inverting input terminal and the inverting input terminal of the operational amplifier are used to receive the audio signal, and the output terminal of the operational amplifier is used to output the single-ended signal.

[0016] According to a power supply control circuit provided by the utility model, the signal conversion circuit further includes an RC low-pass filter circuit, and the output end of the operational amplifier is connected to the signal discrimination circuit through the RC low-pass filter circuit.

[0017] According to a power supply control circuit provided by the utility model, the control subcircuit includes a first switch circuit and a power supply control module;

[0018] The first switch circuit is used to output a first switch signal to the power supply control module according to the high / low level signal;

[0019] The power supply control module is used to control the on / off state between the power supply module and the microprocessor under the triggering of the first switch signal.

[0020] According to a power supply control circuit provided by the utility model, the control subcircuit further includes a second switch circuit;

[0021] The second switch circuit is configured to be connected to the microprocessor to feed back a second switch value signal to the power supply control module under the control of the microprocessor;

[0022] The power supply control module is used to control the power supply module to supply power to the microprocessor under the triggering of the second switch signal.

[0023] In a second aspect, the utility model further provides an audio power amplifier, comprising: a microprocessor and the power supply control circuit as described above; wherein the detection subcircuit and the control subcircuit are electrically connected to the microprocessor respectively.

[0024] According to an audio power amplifier provided by the utility model, it also includes: a signal conditioning module, a digital signal processing module and a power amplification module;

[0025] The signal conditioning module, the digital signal processing module and the power amplification module are connected in sequence, the signal conditioning module is electrically connected to the detection subcircuit, and the microprocessor is electrically connected to the digital signal processing module and the power amplification module respectively;

[0026] The signal conditioning module is used to receive at least one audio signal, and the detection subcircuit is used to receive the audio signal processed by the signal conditioning module.

[0027] In a third aspect, the utility model further provides an audio system, comprising: a pickup, the audio power amplifier as described above, and a speaker;

[0028] The pickup is electrically connected to the signal conditioning module, and the power amplification module is electrically connected to the speaker.

[0029] The power supply control circuit, audio power amplifier and audio system provided by the utility model can, by configuring a detection subcircuit and a control subcircuit, when the audio power amplifier receives an audio signal, the detection subcircuit outputs a high-level signal to the control subcircuit and the microprocessor respectively, the control subcircuit controls the power supply module to supply power to the microprocessor, and the microprocessor controls the audio power amplifier to be in a working state; and when the audio power amplifier does not receive an audio signal, the detection subcircuit outputs a low-level signal to the control subcircuit and the microprocessor respectively, the control subcircuit controls the power supply module to stop supplying power to the microprocessor, and the microprocessor controls the audio power amplifier to be in a power-off state.

[0030] It can be seen that the power supply control circuit shown in the utility model controls the audio power amplifier to switch between the power-off state and the working state by detecting the audio signal. This design not only ensures that the audio power amplifier can work normally, but also effectively reduces the problem of high power consumption of the existing audio power amplifier when in standby mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 This is a control structure block diagram of the audio power amplifier provided by the utility model;

[0033] Figure 2 It is a circuit principle diagram of the detection sub-circuit provided by the utility model;

[0034] Figure 3 It is a circuit schematic diagram of the control subcircuit provided by the utility model;

[0035] Figure 4 It is a circuit schematic diagram of a signal conditioning unit in the signal conditioning module provided by the utility model;

[0036] Reference numerals:

[0037] 1. Detection subcircuit; 11. Signal conversion circuit; 12. Signal discrimination circuit;

[0038] 2. Control subcircuit; 21. First switch circuit; 22. Power supply control module; 23. Second switch circuit;

[0039] 3. Microprocessor; 4. Power supply module; 5. Signal conditioning module; 6. Digital signal processing module; 7. Power amplifier module. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be clearly and completely described below in conjunction with the drawings in the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0041] Combine the following Figure 1-Figure 4 , the power supply control circuit, audio power amplifier and audio system provided by the embodiments of the utility model are described in detail through specific embodiments and their application scenarios.

[0042] In the first aspect, Figure 1 As shown, an embodiment of the utility model provides a power supply control circuit, comprising:

[0043] The detection subcircuit 1 is used to detect whether the audio power amplifier receives an audio signal, and output a high / low level signal to the control subcircuit 2 and the microprocessor 3 respectively according to the detection result.

[0044] The control subcircuit 2 is used to control the power supply state of the power module 4 to the microprocessor 3 according to the high / low level signal.

[0045] The microprocessor 3 is configured to control the audio power amplifier to switch between the standby state and the working state according to the high / low level signal.

[0046] It is understandable that the detection subcircuit 1 is configured to be connected to the audio signal input terminal of the audio power amplifier to detect whether the audio power amplifier receives the audio signal.

[0047] The detection subcircuit 1 is used to provide a detection channel for the transmission of audio signals, and a logic processing chip is configured for the detection channel. When there is an audio signal at the audio signal input end, the detection channel transmits the audio signal to the logic processing chip, and the logic processing chip outputs a high-level signal to indicate that the audio power amplifier has received the audio signal; when there is no audio signal at the audio signal input end, the detection channel cannot transmit the audio signal, and the logic processing chip outputs a low-level signal to indicate that the audio power amplifier has not received the audio signal.

[0048] At the same time, the control subcircuit 2 is electrically connected to the detection subcircuit 1 and is configured to be connected in series between the power module 4 and the microprocessor 3. The control subcircuit 2 can adopt a switch control circuit known in the art, and the control subcircuit 2 can make different response actions according to the received high level signal or low level signal.

[0049] Optionally, when a high-level signal is received, the control subcircuit 2 may be set to be in an on state, and correspondingly, when a low-level signal is received, the control subcircuit 2 may be set to be in an off state.

[0050] Of course, when a high-level signal is received, the control subcircuit 2 can also be set to be in the cut-off state, and correspondingly, when a low-level signal is received, the control subcircuit 2 is in the on state.

[0051] The power supply control circuit provided by the utility model can, by configuring a detection subcircuit 1 and a control subcircuit 2, when the audio power amplifier receives an audio signal, the detection subcircuit 1 outputs a high-level signal to the control subcircuit 2 and the microprocessor 3 respectively, the control subcircuit 2 controls the power module 4 to supply power to the microprocessor 3, and the microprocessor 3 controls the audio power amplifier to be in a working state; when the audio power amplifier does not receive an audio signal, the detection subcircuit 1 outputs a low-level signal to the control subcircuit 2 and the microprocessor 3 respectively, the control subcircuit 2 controls the power module 4 to stop supplying power to the microprocessor 3, and the microprocessor 3 controls the audio power amplifier to be in a power-off state.

[0052] It can be seen that the power supply control circuit shown in the utility model controls the audio power amplifier to switch between the power-off state and the working state by detecting the audio signal. This design not only ensures that the audio power amplifier can work normally, but also effectively reduces the problem of high power consumption of the existing audio power amplifier when in standby mode.

[0053] In some embodiments, Figure 1As shown, the detection subcircuit 1 includes a signal conversion circuit 11 and a signal discrimination circuit 12 .

[0054] The signal conversion circuit 11 is used to convert the audio signal into a single-ended signal; the signal identification circuit 12 is used to identify the category of the single-ended signal and output a high / low level signal corresponding to the category.

[0055] It is understandable that the audio signal is usually a differential signal. The signal conversion circuit 11 converts the differential audio signal into a single-ended signal, so that the signal discrimination circuit 12 can identify the type of the single-ended signal to determine whether the audio power amplifier receives the audio signal.

[0056] In practical applications, the signal conversion circuit 11 may use an operational amplifier or a signal conversion chip SN65EPT21D known in the art to achieve conversion of audio signals into single-ended signals.

[0057] The signal discrimination circuit 12 may adopt an audio signal processor known in the art. The C-MOS comparator built into the audio signal processor can identify the type of the single-ended signal and make a corresponding output response according to the discrimination result.

[0058] When the signal conversion circuit 11 receives an audio signal, the signal conversion circuit 11 will output a single-ended signal. At this time, after receiving the single-ended signal, the signal identification circuit 12 will determine that the audio power amplifier receives the audio signal and output a high-level signal (for example, 1V).

[0059] When the signal conversion circuit 11 does not receive an audio signal, the signal conversion circuit 11 will not output a single-ended signal, or it can be considered that the input end of the signal discrimination circuit 12 receives a single-ended signal of 0V. At this time, the signal discrimination circuit 12 will determine that the audio power amplifier does not receive an audio signal and output a low-level signal (for example, 0V).

[0060] In some embodiments, Figure 1 and Figure 2 As shown, the signal conversion circuit 11 is configured with multiple channels; the multiple-channel signal conversion circuit 11 is configured to perform one-to-one processing on the multiple-channel audio signals, and the multiple-channel signal conversion circuit 11 is commonly connected to a signal discrimination circuit 12 .

[0061] It can be understood that since the multi-channel signal conversion circuit 11 is connected to a signal discrimination circuit 12, the multi-channel signal conversion circuit 11 superimposes and couples the multi-channel audio signals to ensure that any channel in the multi-channel signal conversion circuit 11 will output a single-ended signal when receiving an audio signal, and the signal discrimination circuit 12 outputs a high / low level signal according to the received single-ended signal.

[0062] like Figure 1 and Figure 2 As shown, when the audio power amplifier receives four-channel audio signals, the signal conditioning module 5 of the audio power amplifier performs signal conditioning on the four-channel audio signals respectively, and the four-channel audio signals after signal conditioning are transmitted one by one to the four-channel signal conversion circuit 11, and the four-channel signal conversion circuit 11 performs signal conversion processing on the four-channel audio signals respectively, and transmits the single-ended signals obtained after processing to the signal discrimination circuit 12.

[0063] like Figure 2 As shown, the signal conversion circuit 11 uses an operational amplifier to perform signal conversion processing on the audio signal to obtain an output single-ended signal.

[0064] Specifically, the non-inverting input terminal and the inverting input terminal of the operational amplifier are used to receive the audio signal, and the output terminal of the operational amplifier is used to output a single-ended signal.

[0065] Among them, for each signal conversion circuit 11, the in-phase input terminal and the inverting input terminal of the operational amplifier are both provided with DC blocking capacitors to remove the DC signal in the audio signal when the audio signal is input in a differential form, thereby ensuring that the output terminal of the operational amplifier stably outputs a single-ended signal.

[0066] Furthermore, the signal conversion circuit 11 further includes an RC low-pass filter circuit, and the output end of the operational amplifier is connected to the signal discrimination circuit 12 via the RC low-pass filter circuit.

[0067] It can be understood that the RC low-pass filter circuit is connected in series to the output end of the operational amplifier and the signal discrimination circuit 12 , and the RC low-pass filter circuit is formed by a resistor and a capacitor connected in series.

[0068] Since the operational amplifier outputs an alternating single-ended signal, the RC low-pass filter circuit performs low-pass filtering on the single-ended signal to further obtain a single-ended signal below the cutoff frequency so that the single-ended signal meets the signal processing requirements of the signal discrimination circuit 12.

[0069] In some embodiments, Figure 1 The control subcircuit 2 includes a first switch circuit 21 and a power supply control module 22 .

[0070] The first switch circuit 21 is used to output a first switch signal to the power supply control module 22 according to the high / low level signal; the power supply control module 22 is used to control the on / off state between the power supply module 4 and the microprocessor 3 under the triggering of the first switch signal.

[0071] like Figure 3As shown, the first switch circuit 21 can be built based on the transistor Q1, the output end of the signal discrimination circuit 12 is connected to the base of the transistor Q1, the emitter of the transistor Q1 is grounded, and the collector of the transistor Q1 is connected to the CTL port of the power supply control module 22.

[0072] The power module 4 is connected to the VCC port of the power supply control module 22, and the VO port of the power supply control module 22 is electrically connected to the microprocessor 3. The power supply control module 22 is a power management chip with 8 pins known in the art.

[0073] When the signal discrimination circuit 12 outputs a high-level signal to the base of the transistor Q1, the transistor Q1 is turned on, and under the triggering of the first switching signal fed back when the transistor Q1 is turned on, the VCC port and the VO port of the power supply control module 22 are connected, thereby realizing that the power supply module 4 provides working power to the microprocessor 3.

[0074] Correspondingly, when the signal discrimination circuit 12 outputs a low-level signal to the base of the transistor Q1, the transistor Q1 is cut off, and the power supply control module 22 will not receive the trigger signal from the transistor Q1, causing the VCC port and the VO port of the power supply control module 22 to be in the cut-off state, so that the power supply module 4 will not provide working power to the microprocessor 3.

[0075] In some embodiments, Figure 3 As shown, the control subcircuit 2 further includes a second switch circuit 23 .

[0076] The second switch circuit 23 is configured to be connected to the microprocessor 3 so as to feed back the second switch value signal to the power supply control module 22 under the control of the microprocessor 3 .

[0077] The power supply control module 22 is used to control the power supply module 4 to supply power to the microprocessor 3 under the triggering of the second switch signal.

[0078] It is understandable that since the switching state of the first switch circuit 21 is affected by the high / low level signal output by the signal discrimination circuit 12, after the microprocessor 3 is powered on, in order to prevent the audio power amplifier from not receiving the audio signal for a short period of time, causing the first switch circuit 21 to switch to the open circuit state, thereby causing the microprocessor 3 to switch to the power-off state, this embodiment designs the second switch circuit 23 to maintain control of the power supply state of the microprocessor 3 after the microprocessor 3 is powered on.

[0079] Specifically, after the microprocessor 3 is powered on, the microprocessor 3 outputs a control signal (for example, a high-level signal) to the second switch circuit 23. The second switch circuit 23 is turned on under the control of the control signal, and feeds back a second trigger signal to the power supply control module 22. Under the triggering of the second trigger signal, the VCC port and the VO port of the power supply control module 22 remain connected, and the working state of the power supply control module 22 is no longer affected by the switching state of the first switch circuit 21, unless the microprocessor 3 receives a low-level signal output by the signal discrimination circuit 12 again. At this time, the microprocessor 3 controls the second switch circuit 23 to be in a disconnected state to release the second switch circuit 23 from maintaining control over the power supply state of the power supply control module 22.

[0080] like Figure 3 As shown, the second switch circuit 23 can be constructed based on the transistor Q2, the control pin of the microprocessor 3 is connected to the base of the transistor Q2, the emitter of the transistor Q2 is grounded, and the collector of the transistor Q2 is connected to the CTL port of the power supply control module 22. Obviously, the switching state of the transistor Q2 is affected by the control signal output by the microprocessor 3, which will not be described one by one here.

[0081] In the second aspect, Figure 1 As shown, the utility model further provides an audio power amplifier, comprising: a microprocessor 3 and the above power supply control circuit; wherein the detection subcircuit 1 and the control subcircuit 2 are electrically connected to the microprocessor 3 respectively.

[0082] It can be understood that since the audio power amplifier includes a power supply control circuit, and the specific structure of the power supply control circuit refers to the above embodiment, the audio power amplifier of this embodiment includes all the technical solutions of the above embodiment, and therefore, at least has all the beneficial effects achieved by all the technical solutions of the above embodiment, which will not be repeated here one by one.

[0083] In some embodiments, Figure 1 As shown, the audio power amplifier further includes: a signal conditioning module 5 , a digital signal processing module 6 and a power amplification module 7 .

[0084] The signal conditioning module 5, the digital signal processing module 6 and the power amplification module 7 are connected in sequence, the signal conditioning module 5 and the detection subcircuit 1 are electrically connected, and the microprocessor 3 is electrically connected to the digital signal processing module 6 and the power amplification module 7 respectively.

[0085] The signal conditioning module 5 is used to receive at least one audio signal, and the detection subcircuit 1 is used to receive the audio signal processed by the signal conditioning module 5 .

[0086] It is understandable that the digital signal processing module 6 includes an analog-to-digital conversion unit, a signal processing unit and a digital-to-analog conversion unit, and the signal conditioning module 5, the analog-to-digital conversion unit, the signal processing unit, the digital-to-analog conversion unit and the power amplification module 7 are connected in sequence.

[0087] At the same time, according to the number of audio signals received by the audio power amplifier, the signal conditioning module 5 is configured with a corresponding number of signal conditioning units.

[0088] Optionally, when the audio power amplifier is configured to receive four audio signals, namely, audio signal 1, audio signal 2, audio signal 3 and audio signal 4, the signal conditioning module 5 is configured with four signal conditioning units, which perform signal conditioning on the four audio signals one by one.

[0089] like Figure 4 As shown, for each signal conditioning unit, the signal conditioning unit filters out the DC signal with bias in the received audio signal and then transmits the useful audio signal in differential form to the analog-to-digital conversion unit and the above-mentioned signal conversion circuit 11 respectively.

[0090] In a third aspect, an embodiment of the utility model further provides an audio system, comprising: a pickup, the audio power amplifier as described above, and a speaker.

[0091] The pickup is electrically connected to the signal conditioning module 5 , and the power amplification module 7 is electrically connected to the speaker.

[0092] It is understandable that a plurality of microphones can be provided, and the plurality of microphones can be provided at different positions on the locomotive, and the plurality of microphones respectively transmit the collected multi-channel audio signals to the signal conditioning unit of the audio power amplifier.

[0093] Among them, since the audio system includes an audio power amplifier, the specific structure of the audio power amplifier refers to the above embodiment, and the audio system of this embodiment includes all the technical solutions of the above embodiment, and therefore at least has all the beneficial effects achieved by all the technical solutions of the above embodiment, which will not be repeated here one by one.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A power supply control circuit, characterized in that: include: The detection subcircuit is used to detect whether the audio power amplifier receives the audio signal, and output high / low level signals to the control subcircuit and the microprocessor respectively according to the detection result; A control subcircuit, used for controlling the power supply state of the power module to the microprocessor according to the high / low level signal; Wherein, the microprocessor is configured to control the audio power amplifier to switch between a power-off state and a working state according to the high / low level signal.

2. The power supply control circuit according to claim 1, characterized in that: The detection subcircuit includes a signal conversion circuit and a signal discrimination circuit; The signal conversion circuit is used to convert the audio signal into a single-ended signal; The signal discrimination circuit is used to identify the category of the single-ended signal and output the high / low level signal corresponding to the category.

3. The power supply control circuit according to claim 2, characterized in that: The signal conversion circuit is configured with multiple channels; The multiple signal conversion circuits are configured to process the multiple audio signals in a one-to-one correspondence, and the multiple signal conversion circuits are commonly connected to one signal identification circuit.

4. The power supply control circuit according to claim 2, characterized in that: The signal conversion circuit includes an operational amplifier; The non-inverting input terminal and the inverting input terminal of the operational amplifier are used to receive the audio signal, and the output terminal of the operational amplifier is used to output the single-ended signal.

5. The power supply control circuit according to claim 4, characterized in that: The signal conversion circuit also includes an RC low-pass filter circuit, and the output end of the operational amplifier is connected to the signal discrimination circuit through the RC low-pass filter circuit.

6. The power supply control circuit according to any one of claims 2 to 5, characterized in that: The control subcircuit includes a first switch circuit and a power supply control module; The first switch circuit is used to output a first switch signal to the power supply control module according to the high / low level signal; The power supply control module is used to control the on-off state between the power supply module and the microprocessor under the triggering of the first switch signal.

7. The power supply control circuit according to claim 6, characterized in that: The control subcircuit also includes a second switch circuit; The second switch circuit is configured to be connected to the microprocessor to feed back a second switch value signal to the power supply control module under the control of the microprocessor; The power supply control module is used to control the power supply module to supply power to the microprocessor under the triggering of the second switch signal.

8. An audio power amplifier, characterized in that: include: A microprocessor and a power supply control circuit as claimed in any one of claims 1 to 7; Wherein, the detection subcircuit and the control subcircuit are electrically connected to the microprocessor respectively.

9. The audio power amplifier according to claim 8, characterized in that: Also includes: Signal conditioning module, digital signal processing module and power amplifier module; The signal conditioning module, the digital signal processing module and the power amplification module are connected in sequence, the signal conditioning module and the detection subcircuit are electrically connected, and the microprocessor is electrically connected to the digital signal processing module and the power amplification module respectively; The signal conditioning module is used to receive at least one audio signal, and the detection subcircuit is used to receive the audio signal processed by the signal conditioning module.

10. An audio system, characterized in that: include: A pickup, an audio power amplifier and a loudspeaker as claimed in claim 9; The pickup is electrically connected to the signal conditioning module, and the power amplification module is electrically connected to the speaker.

Images