Power-off POP sound suppression circuit, electronic equipment and controller

Abstract

The utility model provides a power-off POP sound suppression circuit, which comprises an AC-to-DC output circuit, an audio power amplifier chip, an optocoupler U1 and a triode Q1, the anode of a light emitting diode of the optocoupler U1 is electrically connected with an AC input end, the base of a phototriode of the optocoupler U1 is over against the light emitting diode, and the cathode of the phototriode of the optocoupler U1 is electrically connected with the AC input end. A collector electrode of a phototriode of the optocoupler U1 is electrically connected with the direct current output end; the base electrode of the triode Q1 is electrically connected with the collector electrode of the photoelectric triode, and the collector electrode of the triode Q1 is electrically connected with the DC output end and the detection end of the audio power amplifier chip. When an input voltage drops to a set voltage, the optocoupler U1 outputs a high level, the triode Q1 outputs a low level, the detection end of the audio power amplifier chip can detect the low level at the moment, the audio power amplifier chip is controlled to enter a mute mode in advance, and the working voltage of the whole system is still in a normal range at the moment. At the moment, the input voltage continues to be powered off, and the POP sound can be inhibited due to the fact that the system enters the mute mode in advance.

Description

Technical Field

[0001] The utility model relates to the field of electronic technology, and in particular to a power-off POP sound suppression circuit, electronic equipment and a controller. Background Art

[0002] In order to prevent electronic devices from generating POP sounds when power is suddenly cut off during audio playback, a power-off POP sound suppression circuit is usually set.

[0003] In the prior art, the power-off POP sound suppression circuit quickly sets the speaker to a mute module in advance when the output voltage drops to a set amplitude. However, if the electronic device gradually drops to a low voltage, the amplitude of the drop will not reach the set amplitude mentioned above. When the electronic device is powered off from the low voltage again, it will not be able to react quickly because the amplitude of the drop will not reach the set amplitude mentioned above, and POP sound will still be generated. Therefore, how to suppress the generation of POP sound under low voltage conditions has become a technical problem that needs to be solved urgently. Utility Model Content

[0004] In order to solve the above problems, the utility model proposes a power-off POP sound suppression circuit, an electronic device and a controller.

[0005] In the first aspect, the utility model provides a power-off POP sound suppression circuit, including an AC alternating current conversion DC direct current output circuit and an audio power amplifier chip, wherein the AC alternating current conversion DC direct current output circuit includes an AC input terminal and a DC output terminal, the audio power amplifier chip includes a power supply terminal, the DC output terminal is electrically connected to the power supply terminal, and the circuit further includes:

[0006] An optical coupler U1, wherein an anode of a light emitting diode of the optical coupler U1 is electrically connected to the AC input terminal, a cathode of the light emitting diode of the optical coupler U1 is grounded, a base of a phototransistor of the optical coupler U1 is directly opposite to the light emitting diode, an emitter of the phototransistor of the optical coupler U1 is grounded, and a collector of the phototransistor of the optical coupler U1 is electrically connected to the DC output terminal;

[0007] The transistor Q1 has a base electrically connected to the collector of the phototransistor, a collector electrically connected to the DC output terminal and a detection terminal of the audio power amplifier chip, and an emitter of the transistor Q1 is grounded.

[0008] Beneficial effects:

[0009] The utility model sets the optocoupler U1 and the transistor Q1. When the voltage is in a normal state, the optocoupler U1 will output a low level, so that the transistor Q1 will output a high level. At this time, the detection end can detect the high level. When the input voltage drops to the set voltage, the optocoupler U1 will output a high level, and the transistor Q1 will output a low level. At this time, the detection end of the audio power amplifier chip can detect the low level, and the audio power amplifier chip will be controlled to enter the mute mode in advance. At this time, the operating voltage of the entire system is still within the normal range. At this time, if the input voltage continues to be powered off, the mute mode is entered in advance, and the generation of POP sound can be suppressed. Therefore, the utility model provides a hardware architecture that can help suppress the generation of POP sound of electronic equipment under low voltage conditions.

[0010] Furthermore, the circuit also includes a buck rectifier circuit, a first end of the buck rectifier circuit is electrically connected to the AC input end, and a second end of the buck rectifier circuit is electrically connected to the anode of the light emitting diode.

[0011] Further, the step-down rectifier circuit includes a first resistor R1, a first diode D1 and a first capacitor E1;

[0012] One end of the first resistor R1 is electrically connected to the AC input end, the other end of the first resistor R1 is electrically connected to the anode of the first diode D1, the cathode of the first diode D1 is electrically connected to the anode of the light-emitting diode and the positive electrode of the first capacitor E1, and the negative electrode of the first capacitor E1 is grounded.

[0013] Furthermore, the circuit also includes a buck stabilizing circuit, a first end of the buck stabilizing circuit is electrically connected to a second end of the buck rectifier circuit, and a second end of the buck stabilizing circuit is electrically connected to an anode of the light emitting diode.

[0014] Furthermore, the circuit also includes a current limiting resistor R2, one end of the current limiting resistor R2 is electrically connected to the second end of the step-down voltage stabilization circuit, and the other end of the current limiting resistor R2 is electrically connected to the anode of the light emitting diode.

[0015] Furthermore, the circuit further comprises a step-down voltage stabilizing circuit, and the step-down voltage stabilizing circuit comprises a fourth resistor R4, a sixth resistor R6 and a voltage stabilizing diode ZD1;

[0016] One end of the fourth resistor R4 is electrically connected to the cathode of the first diode D1, and the other end of the fourth resistor R4 is electrically connected to the anode of the light emitting diode;

[0017] One end of the sixth resistor R6 is electrically connected to the anode of the light emitting diode, and the other end of the sixth resistor R6 is grounded;

[0018] The cathode of the voltage stabilizing diode ZD1 is electrically connected to the anode of the light emitting diode, and the anode of the voltage stabilizing diode ZD1 is grounded.

[0019] Furthermore, the circuit further comprises a third resistor R3, one end of the third resistor R3 is electrically connected to the DC output end, and the other end of the third resistor R3 is electrically connected to the base of the transistor Q1 and the collector of the phototransistor.

[0020] Furthermore, the circuit further comprises a fifth resistor R5, one end of the fifth resistor R5 is electrically connected to the DC output end, and the other end of the fifth resistor R5 is electrically connected to the collector of the transistor Q1 and the detection end.

[0021] In a second aspect, the present invention provides a controller of an electronic device, comprising a power-off POP sound suppression circuit as described in any of the above embodiments.

[0022] In a third aspect, the present invention provides an electronic device, comprising a speaker and a controller of the electronic device described in the above embodiment, wherein the control end of the audio power amplifier chip is electrically connected to the speaker. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The utility model is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0024] Figure 1 A circuit diagram of a power-off POP sound suppression circuit provided by the utility model;

[0025] Figure 2 The utility model provides Figure 1 Enlarged diagram of the circuit at point A in the middle. DETAILED DESCRIPTION

[0026] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. It is to be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some structures related to the present application are shown in the accompanying drawings, rather than all structures. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0027] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0028] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0029] In this specification, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being “above”, “above”, and “above” a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0030] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0031] like Figure 1 and Figure 2 As shown, the utility model provides a power-off POP sound suppression circuit, including an AC alternating current conversion DC direct current output circuit and an audio power amplifier chip, the AC alternating current conversion DC direct current output circuit includes an AC input terminal and a DC output terminal, the audio power amplifier chip includes a power supply terminal, the DC output terminal is electrically connected to the power supply terminal, and the circuit also includes:

[0032] An optical coupler U1, wherein an anode of a light emitting diode of the optical coupler U1 is electrically connected to the AC input terminal, a cathode of the light emitting diode of the optical coupler U1 is grounded, a base of a phototransistor of the optical coupler U1 is directly opposite to the light emitting diode, an emitter of the phototransistor of the optical coupler U1 is grounded, and a collector of the phototransistor of the optical coupler U1 is electrically connected to the DC output terminal;

[0033] The transistor Q1 has a base electrically connected to the collector of the phototransistor, a collector electrically connected to the DC output terminal and a detection terminal of the audio power amplifier chip, and an emitter of the transistor Q1 is grounded.

[0034] In this embodiment, through the setting of the optocoupler U1 and the transistor Q1, when the voltage is in a normal state, the optocoupler U1 will output a low level, so that the transistor Q1 will output a high level. At this time, the detection end can detect the high level, and when the input voltage drops to the set voltage, the optocoupler U1 will output a high level, and the transistor Q1 will output a low level. At this time, the detection end of the audio power amplifier chip can detect the low level, and the audio power amplifier chip will be controlled to enter the silent mode in advance, and at this time, the operating voltage of the entire system is still within the normal range. At this time, if the input voltage continues to be powered off, the silent mode is entered in advance, and the generation of POP sound can be suppressed. Therefore, the utility model provides a hardware architecture that can help suppress the generation of POP sound of electronic equipment under low voltage conditions.

[0035] Preferably, the circuit further comprises a buck rectifier circuit, a first end of the buck rectifier circuit is electrically connected to the AC input end, and a second end of the buck rectifier circuit is electrically connected to the anode of the light emitting diode.

[0036] Specifically, the step-down rectifier circuit includes a first resistor R1, a first diode D1 and a first capacitor E1;

[0037] One end of the first resistor R1 is electrically connected to the AC input end, the other end of the first resistor R1 is electrically connected to the anode of the first diode D1, the cathode of the first diode D1 is electrically connected to the anode of the light-emitting diode and the positive electrode of the first capacitor E1, and the negative electrode of the first capacitor E1 is grounded.

[0038] When powered on, the AC power connected to the AC input terminal is stepped down by the first resistor R1, rectified by the first diode D1, and finally filtered by the first capacitor E1.

[0039] Preferably, the circuit further comprises a buck stabilizing circuit, a first end of the buck stabilizing circuit is electrically connected to a second end of the buck rectifier circuit, and a second end of the buck stabilizing circuit is electrically connected to an anode of the light emitting diode.

[0040] Among them, the buck rectifier circuit can be connected to the anode of the light emitting diode through the buck voltage stabilizing circuit to achieve the two purposes of buck rectification and buck voltage stabilization.

[0041] Preferably, the circuit further comprises a current limiting resistor R2, one end of the current limiting resistor R2 is electrically connected to the second end of the step-down voltage stabilizing circuit, and the other end of the current limiting resistor R2 is electrically connected to the anode of the light emitting diode.

[0042] Specifically, the step-down voltage stabilization circuit is connected to the anode of the light emitting diode via the current limiting resistor R2, so as to prevent the light emitting diode from being damaged when the voltage is too high.

[0043] Preferably, the circuit further comprises a step-down voltage stabilizing circuit, and the step-down voltage stabilizing circuit comprises a fourth resistor R4, a sixth resistor R6 and a voltage stabilizing diode ZD1;

[0044] One end of the fourth resistor R4 is electrically connected to the cathode of the first diode D1, and the other end of the fourth resistor R4 is electrically connected to the anode of the light emitting diode;

[0045] One end of the sixth resistor R6 is electrically connected to the anode of the light emitting diode, and the other end of the sixth resistor R6 is grounded;

[0046] The cathode of the voltage stabilizing diode ZD1 is electrically connected to the anode of the light emitting diode, and the anode of the voltage stabilizing diode ZD1 is grounded.

[0047] Specifically, the cathode of the first diode D1 is connected to the anode of the light emitting diode through the fourth resistor R4, so as to achieve the two purposes of step-down rectification and step-down voltage stabilization. It should be noted that the cathode of the first diode D1 can also be connected to the anode of the light emitting diode through the fourth resistor R4 and the current limiting resistor R2, so as to achieve the three purposes of step-down rectification, step-down voltage stabilization and further ensuring circuit safety.

[0048] In order to further ensure the circuit safety of the phototransistor and the transistor Q1, preferably, the circuit also includes a third resistor R3, one end of the third resistor R3 is electrically connected to the DC output end, and the other end of the third resistor R3 is electrically connected to the base of the transistor Q1 and the collector of the phototransistor.

[0049] Preferably, the circuit further includes a fifth resistor R5, one end of the fifth resistor R5 is electrically connected to the DC output end, and the other end of the fifth resistor R5 is electrically connected to the collector of the transistor Q1 and the detection end.

[0050] In this embodiment, a controller of an electronic device is also provided, comprising a power-off POP sound suppression circuit as described in any of the above embodiments.

[0051] The controller provided in this embodiment is configured by the optocoupler U1 and the transistor Q1. When the voltage is in a normal state, the optocoupler U1 will output a low level, so that the transistor Q1 will output a high level. At this time, the detection end can detect the high level. When the input voltage drops to the set voltage, the optocoupler U1 will output a high level, and the transistor Q1 will output a low level. At this time, the detection end of the audio power amplifier chip can detect the low level, and the audio power amplifier chip will be controlled to enter the silent mode in advance. At this time, the operating voltage of the entire system is still within the normal range. At this time, if the input voltage continues to be powered off, the silent mode is entered in advance, and the generation of POP sound can be suppressed. Therefore, the utility model provides a controller that can help suppress the generation of POP sound of electronic equipment under low voltage conditions.

[0052] The present invention provides an electronic device, comprising a speaker and a controller of the electronic device described in the above embodiment, wherein the control end of the audio power amplifier chip is electrically connected to the speaker.

[0053] The electronic device provided in this embodiment is configured with an optocoupler U1 and a transistor Q1. When the voltage is in a normal state, the optocoupler U1 will output a low level, thereby the transistor Q1 will output a high level. At this time, the detection end can detect the high level. When the input voltage drops to the set voltage, the optocoupler U1 will output a high level, while the transistor Q1 will output a low level. At this time, the detection end of the audio power amplifier chip can detect the low level, and the audio power amplifier chip will be controlled to enter the mute mode in advance. At this time, the operating voltage of the entire system is still within the normal range. At this time, if the input voltage continues to be powered off, the generation of POP sound can be suppressed due to the early entry into the mute mode.

[0054] It should be noted that the terms "horizontal", "vertical" and the like do not mean that the components are absolutely horizontal or vertical, but can be slightly tilted; the terms "parallel", "vertical" and the like do not mean that the components are absolutely parallel or vertical, but can form a certain angle deviation. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In addition, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of the present application is usually placed when used, which is only for the convenience of describing the embodiments of the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application.

[0055] It is to be understood that the meaning of "plurality" herein is at least two, such as two, three, etc., unless there is a special limitation. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or devices. The term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " herein generally indicates that the associated objects before and after are in an "or" relationship.

[0056] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A power-off POP sound suppression circuit, comprising an AC conversion DC output circuit and an audio power amplifier chip, wherein the AC conversion DC output circuit comprises an AC input terminal and a DC output terminal, and the audio power amplifier chip comprises a power supply terminal, and the DC output terminal is electrically connected to the power supply terminal, characterized in that: The circuit further comprises: An optical coupler U1, wherein an anode of a light emitting diode of the optical coupler U1 is electrically connected to the AC input terminal, a cathode of the light emitting diode of the optical coupler U1 is grounded, a base of a phototransistor of the optical coupler U1 is directly opposite to the light emitting diode, an emitter of the phototransistor of the optical coupler U1 is grounded, and a collector of the phototransistor of the optical coupler U1 is electrically connected to the DC output terminal; The transistor Q1 has a base electrically connected to the collector of the phototransistor, a collector electrically connected to the DC output terminal and a detection terminal of the audio power amplifier chip, and an emitter of the transistor Q1 is grounded.

2. A power-off POP sound suppression circuit according to claim 1, characterized in that: The circuit further comprises a buck rectifier circuit, a first end of the buck rectifier circuit is electrically connected to the AC input end, and a second end of the buck rectifier circuit is electrically connected to the anode of the light emitting diode.

3. A power-off POP sound suppression circuit according to claim 2, characterized in that: The step-down rectifier circuit includes a first resistor R1, a first diode D1 and a first capacitor E1; One end of the first resistor R1 is electrically connected to the AC input end, the other end of the first resistor R1 is electrically connected to the anode of the first diode D1, the cathode of the first diode D1 is electrically connected to the anode of the light-emitting diode and the positive electrode of the first capacitor E1, and the negative electrode of the first capacitor E1 is grounded.

4. A power-off POP sound suppression circuit according to claim 2 or 3, characterized in that: The circuit also includes a buck stabilizing circuit, a first end of the buck stabilizing circuit is electrically connected to a second end of the buck rectifier circuit, and a second end of the buck stabilizing circuit is electrically connected to an anode of the light emitting diode.

5. A power-off POP sound suppression circuit according to claim 4, characterized in that: The circuit further includes a current limiting resistor R2, one end of the current limiting resistor R2 is electrically connected to the second end of the step-down voltage stabilization circuit, and the other end of the current limiting resistor R2 is electrically connected to the anode of the light emitting diode.

6. A power-off POP sound suppression circuit according to claim 3, characterized in that: The circuit further includes a step-down voltage stabilizing circuit, and the step-down voltage stabilizing circuit includes a fourth resistor R4, a sixth resistor R6 and a voltage stabilizing diode ZD1; One end of the fourth resistor R4 is electrically connected to the cathode of the first diode D1, and the other end of the fourth resistor R4 is electrically connected to the anode of the light emitting diode; One end of the sixth resistor R6 is electrically connected to the anode of the light emitting diode, and the other end of the sixth resistor R6 is grounded; The cathode of the voltage stabilizing diode ZD1 is electrically connected to the anode of the light emitting diode, and the anode of the voltage stabilizing diode ZD1 is grounded.

7. A power-off POP sound suppression circuit according to claim 1, characterized in that: The circuit further includes a third resistor R3, one end of the third resistor R3 is electrically connected to the DC output end, and the other end of the third resistor R3 is electrically connected to the base of the transistor Q1 and the collector of the phototransistor.

8. The power-off POP sound suppression circuit according to claim 1, characterized in that: The circuit further includes a fifth resistor R5, one end of which is electrically connected to the DC output end, and the other end of which is electrically connected to the collector of the transistor Q1 and the detection end.

9. A controller for an electronic device, characterized in that: It comprises a power-off POP sound suppression circuit as described in any one of claims 1-8.

10. An electronic device, characterized in that: The invention comprises a loudspeaker and a controller of an electronic device as claimed in claim 9, wherein the control end of the audio power amplifier chip is electrically connected to the loudspeaker.

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