Audio converter power amplifier output protection circuit and method and electronic equipment

Abstract

The invention relates to the technical field of audio conversion output protection, and discloses a high-reliability and stable audio converter power amplifier output protection circuit, which comprises switch modules (130, 140) for receiving audio signals output by a power amplification module, a main control module (MCU), driving modules (180a, 180b) and a virtual load module (170), when the load is not connected to the output end of the power amplification module, the main control module (MCU) outputs a high-level control signal to trigger the driving modules (180a and 180b) to control the virtual load module (170) to be connected to the output end of the power amplification module.

Description

Technical Field

[0001] The present invention relates to the technical field of audio conversion output protection, and more specifically, to an audio converter power amplifier output protection circuit, method and electronic equipment. Background Art

[0002] When there are different audio devices or interface types in the usage scenario, the output audio signals may be incompatible, and using an audio converter to solve the incompatibility of audio signals is a more reliable means. At present, when using single-ended\complementary push-pull amplifiers (such as tube amplifiers, etc.) for output conversion, since such amplifier outputs cannot work without load, otherwise the amplifier components may be damaged. For example, when multiple interfaces are connected to the amplifier, if any one or two ports of the output interface are unloaded, the port may not be connected to a load, thus causing the problem of no-load damage to the amplifier components (such as the power amplifier).

[0003] Therefore, how to avoid damage to power amplifier components due to no-load to improve the reliability of audio converter operation has become a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0004] The technical problem to be solved by the present invention is that, in view of the defect in the prior art that when using a single-ended\complementary push-pull amplifier (such as a tube amplifier, etc.) for output conversion, the output of such amplifier cannot work at no-load, otherwise the amplifier components may be damaged, a highly reliable and stable audio converter amplifier output protection circuit is provided.

[0005] The technical solution adopted by the present invention to solve the technical problem is: construct an audio converter amplifier output protection circuit, which has:

[0006] At least one set of switch modules, used for receiving the audio signal output by the power amplifier module;

[0007] a main control module, whose signal end is connected to one end of the switch module, and is used to detect a load signal at any output end of the power amplifier module and control the output level according to the load signal;

[0008] at least one set of driving modules, whose input end is connected to the output end of the main control module and is used to receive the control level;

[0009] at least one set of virtual load modules, one input end of which is coupled to the output end of the driving module,

[0010] One end of the virtual load module is connected to the output end of the power amplifier module;

[0011] When the output end of the power amplifier module is not connected to a load, the main control module outputs a high-level control signal to trigger the driving module to control the virtual load module to connect to the output end of the power amplifier module.

[0012] In some embodiments, the switch module includes a first switch circuit and a second switch circuit connected in parallel.

[0013] One end of the first switch circuit is connected to one end of the power amplifier module,

[0014] The other end of the second switch circuit is connected to the output end of the power amplification module.

[0015] In some embodiments, a signal end of the first switch circuit and a signal end of the second switch circuit are respectively connected to a signal end of the main control module.

[0016] In some embodiments, the first switch circuit includes a first relay and a second relay.

[0017] One end of the first relay and the second relay is connected to one end of the power amplifier module,

[0018] A signal end of the first relay and a signal end of the second relay are respectively connected to a signal end of the main control module.

[0019] In some embodiments, the second switch circuit includes a third relay and a fourth relay.

[0020] One end of the third relay and the fourth relay is connected to the output end of the power amplifier module,

[0021] A signal end of the third relay and a signal end of the fourth relay are respectively connected to a signal end of the main control module.

[0022] In some embodiments, the virtual load module includes a first virtual load and a second virtual load.

[0023] The input ends of the first virtual load and the second virtual load are respectively connected to the output end of the driving module.

[0024] The second end of the first virtual load is connected to one end of an output end of the power amplifier module.

[0025] The third end of the first virtual load is connected to the other end of an output end of the power amplifier module.

[0026] The second end of the second virtual load is connected to one end of an output end of the power amplifier module.

[0027] The third end of the second virtual load is connected to the other end of an output end of the power amplification module.

[0028] In some embodiments, the driving module includes at least a first transistor and a second transistor.

[0029] The base of the first transistor is connected to a signal output terminal of the main control module through a third resistor.

[0030] The collector of the first transistor is connected to the input end of the first virtual load,

[0031] The base of the second transistor is connected to a signal output terminal of the main control module through a fifth resistor.

[0032] The collector of the second transistor is connected to the input end of the second virtual load.

[0033] The emitters of the first transistor and the second transistor are connected to a common end.

[0034] In some implementations, the first transistor and the second transistor are selected as NPN transistors.

[0035] In a second aspect, a protection method includes:

[0036] Receive the audio signal output by the power amplifier module;

[0037] Detecting a load signal at any output end of the power amplifier module, and outputting a control level according to the load signal;

[0038] When the output end of the power amplifier module is not connected to a load, a high-level control signal is output to trigger the driving module to control the virtual load module to connect to the output end of the power amplifier module.

[0039] According to a third aspect, an electronic device has the function of implementing the protection method, wherein the function is implemented by hardware or by hardware executing corresponding software, and the hardware or the software includes one or more modules corresponding to the function.

[0040] In the audio converter power amplifier output protection circuit described in the present invention, a switch module, a main control module, a driving module and a virtual load module are included for receiving the audio signal output by the power amplifier module. When the output end of the power amplifier module is not connected to the load, the main control module outputs a high-level control signal to trigger the driving module to control the virtual load module to connect to the output end of the power amplifier module. Compared with the prior art, when using single-ended / complementary push-pull amplifier output conversion, when any one or two output ports of the power amplifier module are not connected to the load, at this time, the main control module will detect the unloaded port in real time, and trigger the driving module to control the virtual load module to work, so that the unloaded port can be loaded in time to avoid the problem of damaging the power amplifier components due to no load. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0042] Figure 1 It is a circuit diagram of an embodiment of a switch module and a virtual load module provided by the present invention;

[0043] Figure 2 It is a circuit schematic diagram of an embodiment of a driving module provided by the present invention. DETAILED DESCRIPTION

[0044] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0045] like Figure 1-Figure 2 As shown, in the first embodiment of the audio converter power amplifier output protection circuit of the present invention, the audio converter power amplifier output protection circuit 100 includes a power amplification module (110, 120, 150, 160), at least one set of switch modules (130, 140), a main control module MCU, at least one set of virtual load modules 170 and at least one set of driving modules (180a, 180b),

[0046] The input side (corresponding to 110 and 120) and the output side (corresponding to 150 and 160) of the power amplifier module are used to input / output audio signals output by different audio devices / interfaces;

[0047] The switch modules (130, 140) are used to transmit / transition input audio signals;

[0048] The main control module MCU is the core of the protection circuit, which has the functions of signal detection, comparison, analysis, calculation and output level control when connected to the load or not connected to the load;

[0049] When the output side (corresponding to 150, 160) of the power amplifier module is not connected to a load, the virtual load module 170 can be used as a virtual load of the output side (corresponding to 150, 160) of the power amplifier module to avoid damage to the power amplifier components due to no load;

[0050] The driving modules (180a, 180b) are used to receive the control level output by the main control module MCU. When the driving modules (180a, 180b) are controlled to work, the virtual load module 170 can be triggered to act, so that the virtual load module 170 is timely connected to the output side of the power amplifier module (corresponding to 150, 160).

[0051] Specifically, one end of at least one set of switch modules (130, 140) is connected to the output side (corresponding to 110, 120) of the receiving power amplifier module, and is used to receive the audio signal output by the power amplifier module (110, 120) so as to transmit the audio signal to the output side (corresponding to 150, 160) of the power amplifier module;

[0052] A signal end of a main control module MCU is connected to one end of a switch module (130, 140) to detect a signal (i.e. a load signal or a level signal) when any end of the output side (corresponding to 150, 160) of the power amplifier module is connected or not connected to a load, and judges whether any end of the output side (corresponding to 150, 160) of the current power amplifier module is connected to a load according to the acquired load signal or level signal.

[0053] When it is detected that no load is connected to any end of the output side (corresponding to 150, 160) of the power amplifier module, the control level of its output is high level, otherwise it is low level;

[0054] The input end of at least one group of driving modules (180a, 180b) is connected to the output end of the main control module MCU and is used to receive a control level, and the input control level is used to control the on / off of the driving modules (180a, 180b);

[0055] Furthermore, an input terminal of at least one set of virtual load modules 170 is coupled to an output terminal of the driving module (180a, 180b).

[0056] Wherein, one end of the virtual load module 170 is connected to any one end or two output ends of the output side (corresponding to 150, 160) of the power amplifier module;

[0057] When any one end or both output ends of the output side (corresponding to 150, 160) of the power amplifier module are connected to a load, the main control module MCU outputs a low-level control signal, and the drive module (180a, 180b) is turned off;

[0058] When any end or both output ends of the output side (corresponding to 150, 160) of the power amplifier module are not connected to a load, the main control module MCU outputs a high-level control signal, which is used to trigger the drive module (180a, 180b) to work, thereby controlling the virtual load module 170 to connect to any end or both output ends of the output side (corresponding to 150, 160) of the power amplifier module to avoid damage to the power amplifier components due to no-load.

[0059] Specifically, if Figure 1 As shown, the audio signal is input into the switch module (130, 140) via the input side (corresponding to 110, 120) of the power amplifier module, and then output via the output side (corresponding to 150, 160);

[0060] These two ports (corresponding to 150 and 160) can be used in a selective manner, which is convenient for various daily usage scenarios.

[0061] When using a single-ended or complementary push-pull amplifier, when any group of JAL1, JAR1, JBL2 and JBR2 ports of the output end 150 or the output end 160 is selected as the output, a load (such as a speaker) must be connected. When any port of JAL1, JAR1, JBL2 and JBR2 is not connected to a speaker or none of them are connected to a speaker, the main control module MCU detects the signal on one end of the switch module (130, 140) to detect whether any port (corresponding to JAL1, JAR1, JBL2 and JBR2) of the output side (corresponding to 150, 160) of the power amplifier module is connected to the signal generated when the load is connected, and controls the driving module (130, 140) according to the obtained load signal state. 80a, 180b), when any port (corresponding to JAL1, JAR1, JBL2 and JBR2) of the output side (corresponding to 150, 160) of the power amplifier module is not connected to the load, the control level output by the main control module MCU triggers the driving module (180a, 180b) to work, so as to control the virtual load module 170 to connect to any port (corresponding to JAL1, JAR1, JBL2 and JBR2) of the output side (corresponding to 150, 160) of the power amplifier module, so as to avoid damage to the power amplifier components due to no-load, so as to achieve the purpose of protecting the power amplifier, making such a power amplifier more convenient and worry-free to use, thereby improving the reliability and stability of the audio converter;

[0062] On the other hand, it can improve the safety and reliability of the audio system and extend the service life of the audio equipment.

[0063] In some embodiments, Figure 1As shown, in order to improve the performance of the protection circuit, the switch modules (130, 140) can be set as a first switch circuit 130 and a second switch circuit 140, wherein the first switch circuit 130 and the second switch circuit 140 are connected in parallel;

[0064] Specifically, one end of the first switch circuit 130 (corresponding to pins 2, 7, 4, and 5) is connected to one end (corresponding to pins 1 and 2) of the input side of the power amplifier module (corresponding to pins 110 and 120) to receive the audio signal input by the power amplifier module;

[0065] The other end of the second switch circuit 140 (corresponding to pins 2, 7, 4, and 5) is connected to the output side (corresponding to pins 150 and 160) and the output end (corresponding to pins 1 and 2) of the power amplifier module, and the input audio signal is added to the load via the first switch circuit 130 and the second switch circuit 140 via the output side (corresponding to pins 150 and 160) of the power amplifier module.

[0066] In some embodiments, Figure 1 As shown, in order to ensure the reliability of obtaining the load signal, a signal end of the first switch circuit 130 can be connected to a signal end of the main control module MCU, which can be used to obtain the state of the audio signal input; and

[0067] A signal end of the second switch circuit 140 is connected to the signal end of the main control module MCU, and is used to obtain the load signal generated when the load is connected to any port (corresponding to JAL1, JAR1, JBL2 and JBR2) of the output side (corresponding to 150, 160) of the power amplifier module.

[0068] Of course, a signal detection module or a signal amplification module may be provided in the main control module MCU and the first switch circuit 130 and the second switch circuit 140 to enhance the accuracy of signal acquisition.

[0069] In some embodiments, Figure 1 As shown, the first switch circuit 130 includes a first relay RY1 and a second relay RY2, and the relays have the functions of switching and transmitting signals;

[0070] The power supply terminals (corresponding to pins 1 and 8) of the first relay RY1 and the second relay RY2 are respectively connected to the output terminals of the power supply module to provide working power for their operation.

[0071] One end of the first relay RY1 and the second relay RY2 (corresponding to pins 2, 7, 4, and 5) are respectively connected to one end (corresponding to pins 1 and 2) of the output side (corresponding to 110 and 120) of the power amplifier module for receiving audio signals;

[0072] A signal terminal of the first relay RY1 (corresponding to RY1-3LIN+, RY1-3LIN-) is connected to the signal terminal of the main control module MCU.

[0073] A signal end of the second relay RY2 (corresponding to RY2-4RIN+, RY2-4RIN-) is respectively connected to a signal end of the main control module MCU for obtaining the state of the audio signal input.

[0074] In some embodiments, Figure 1 As shown, the second switch circuit 140 includes a third relay RY3 and a fourth relay RY4, and the above relays have the functions of switching and transmitting signals;

[0075] Specifically, one end of the third relay RY3 and the fourth relay RY4 (corresponding to pins 2, 7, 4, and 5) is connected to the output end (corresponding to pins 1 and 2) of the output side (corresponding to 150 and 160) of the power amplifier module, and the input audio signal is transmitted to the output side (corresponding to 150 and 160) of the power amplifier module via the third relay RY3 and the fourth relay RY4;

[0076] A signal terminal of the third relay RY3 (corresponding to RY2-4RIN+, RY2-4RIN-) is connected to the signal terminal of the main control module MCU.

[0077] A signal end of the fourth relay RY4 (corresponding to RY1-3LIN+, RY1-3LIN-) is connected to the signal end of the main control module MCU, and is used to obtain the load signal generated when the load is connected to any port (corresponding to JAL1, JAR1, JBL2 and JBR2) of the output side (corresponding to 150, 160) of the power amplifier module.

[0078] In some embodiments, Figure 1 and Figure 2 As shown, in order to improve the safety of the power amplifier operation, a first virtual load Y5 and a second virtual load Y6 can be set in the virtual load module 170, which are respectively set to 10W virtual loads, and the first resistor R101 and the second resistor R102 are used as virtual loads;

[0079] Specifically, the input end (corresponding to RY5IN) of the first virtual load Y5 is connected to the output end (corresponding to RY5IN) of the driving module (corresponding to 180a) to receive the first trigger signal output by the driving module (corresponding to 180a).

[0080] Among them, one end of the first resistor R101 is connected to one end of the first virtual load Y5 (corresponding to pin 5), and the other end of the first resistor R101 is connected to one end of the first virtual load Y5 (corresponding to pin 8);

[0081] The input end (corresponding to RY6IN) of the second virtual load Y6 is connected to the output end (corresponding to RY6IN) of the driving module (corresponding to 180b) to receive the second trigger signal output by the driving module (corresponding to 180b).

[0082] One end of the second resistor R102 is connected to one end of the second virtual load Y6 (corresponding to pin 5), and the other end of the second resistor R102 is connected to one end of the second virtual load Y6 (corresponding to pin 8);

[0083] Specifically, the second end (corresponding to pins 3 and 4) of the first virtual load Y5 is connected to one end (corresponding to pin 2) of an output end (corresponding to JAR1 and JBR2) of the output side (corresponding to 150 and 160) of the power amplifier module.

[0084] The third end (corresponding to pins 6 and 8) of the first virtual load Y5 is connected to the other end (corresponding to pin 1) of an output end (corresponding to JAR1 and JBR2) of the output side (corresponding to 150 and 160) of the power amplifier module.

[0085] The second end (corresponding to pins 3 and 4) of the second virtual load Y6 is connected to one end (corresponding to pin 2) of an output end (corresponding to JAL1 and JBL2) of the output side (corresponding to 150 and 160) of the power amplifier module.

[0086] The third end of the second virtual load Y6 is connected to the other end (corresponding to pin 2) of an output end (corresponding to JAL1 and JBL2) of the output side (corresponding to 150 and 160) of the power amplifier module.

[0087] When any port (corresponding to JAL1, JAR1, JBL2 and JBR2) on the output side (corresponding to 150, 160) of the power amplifier module is not connected to a load, the control level output by the main control module MCU triggers the driving module (180a, 180b) to work, so as to control the first virtual load Y5 and / or the second virtual load Y6 to be connected to any port (corresponding to JAL1, JAR1, JBL2 and JBR2) on the output side (corresponding to 150, 160) of the power amplifier module, so as to avoid damage to the power amplifier components due to no-load.

[0088] In some embodiments, Figure 2 As shown, the driving module (180a, 180b) comprises at least a first transistor VT101 and a second transistor VT102, wherein the first transistor VT101 and the second transistor VT102 are selected as NPN transistors, both of which have the function of switches;

[0089] Specifically, the base of the first transistor VT101 is connected to a signal output terminal (corresponding to MCU-RIN5) of the main control module MCU through the third resistor R103, and is used to receive a control level;

[0090] The collector of the first transistor VT101 is connected to the input end of the first virtual load Y5 (corresponding to RY5IN).

[0091] Wherein, a fourth resistor R104 is arranged between the base and the emitter of the first transistor VT101, which serves as a pull-down resistor and is used to determine the level of the base of the first transistor VT101;

[0092] The anode of the first diode D101 is connected to the +5V power supply terminal, and the cathode of the first diode D101 is connected to the input terminal (corresponding to RY5IN) of the first virtual load Y5;

[0093] The base of the second transistor VT102 is connected to a signal output terminal (corresponding to MCU-YIN5) of the main control module MCU through the fifth resistor R105, and is used to receive another control level;

[0094] The collector of the second transistor VT102 is connected to the input end of the second virtual load Y6.

[0095] A sixth resistor R106 is provided between the base and the emitter of the second transistor VT102, and serves as a pull-down resistor for determining the level of the base of the second transistor VT102.

[0096] The anode of the second diode D102 is connected to the +5V power supply terminal, and the cathode of the second diode D102 is connected to the input terminal (corresponding to RY6IN) of the second virtual load Y6;

[0097] The emitters of the first transistor VT101 and the second transistor VT102 are connected to the common end respectively.

[0098] When any port (corresponding to JAL1, JAR1, JBL2 and JBR2) on the output side (corresponding to 150, 160) of the power amplifier module is not connected to a load, the main control module MCU outputs two high-level control levels, triggering the first transistor VT101 and / or the second transistor VT102 to turn on, pulling the potential of the first virtual load Y5 and / or the second virtual load Y6 to a low level, so that the first virtual load Y5 and / or the second virtual load Y6 is connected to any port (corresponding to (JAL1, JAR1, JBL2 and JBR2) on the output side (corresponding to 150, 160) of the power amplifier module, so as to avoid damage to the power amplifier components due to no-load.

[0099] In a second aspect, a protection method includes a switch module (130, 140) for receiving an audio signal input from an output side (corresponding to 110, 120) of a power amplifier module, and transmitting the input audio signal to the output side (corresponding to 150, 160) of the power amplifier module;

[0100] The main control module MCU is used to detect whether any output end of the output side of the power amplifier module (corresponding to 150, 160) is connected to the load signal of the load, and analyze / judge any port of the output side of the current power amplifier module (corresponding to 150, 160) according to the load signal. ( JAL1, JAR1, JBL2 and JBR2) are connected to the load status and then output the control level (high / low level);

[0101] When any port (JAL1, JAR1, JBL2 and JBR2) on the output side (corresponding to 150, 160) of the power amplifier module is not connected to a load, the main control module MCU outputs a high-level control signal to trigger the driving module (180a, 180b) to work, thereby controlling the virtual load module 170 to connect to any port (JAL1, JAR1, JBL2 and JBR2) on the output side (corresponding to 150, 160) of the power amplifier module to avoid damage to the power amplifier components due to no-load.

[0102] In a third aspect, an electronic device has the function of implementing a protection method, wherein the function is implemented through hardware (such as a power amplifier module (110, 120, 150, 160), at least one group of switch modules (130, 140), a main control module MCU, at least one group of virtual load modules 170 and at least one group of drive modules (180a, 180b)) or through hardware executing corresponding software, and the hardware or software includes one or more modules corresponding to the function.

[0103] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.

Claims

1. An audio converter power amplifier output protection circuit, characterized in that: have: At least one set of switch modules, used for receiving the audio signal output by the power amplifier module; a main control module, whose signal end is connected to one end of the switch module, and is used to detect a load signal at any output end of the power amplifier module and control the output level according to the load signal; at least one set of driving modules, whose input end is connected to the output end of the main control module and is used to receive the control level; at least one set of virtual load modules, one input end of which is coupled to the output end of the driving module, One end of the virtual load module is connected to the output end of the power amplifier module; When the output end of the power amplifier module is not connected to a load, the main control module outputs a high-level control signal to trigger the driving module to control the virtual load module to connect to the output end of the power amplifier module.

2. The audio converter power amplifier output protection circuit according to claim 1, characterized in that: The switch module includes a first switch circuit and a second switch circuit connected in parallel, One end of the first switch circuit is connected to one end of the power amplifier module, The other end of the second switch circuit is connected to the output end of the power amplification module.

3. The audio converter power amplifier output protection circuit according to claim 2, characterized in that: A signal end of the first switch circuit and a signal end of the second switch circuit are respectively connected to a signal end of the main control module.

4. The audio converter power amplifier output protection circuit according to claim 3, characterized in that: The first switch circuit includes a first relay and a second relay, One end of the first relay and the second relay is connected to one end of the power amplifier module, A signal end of the first relay and a signal end of the second relay are respectively connected to a signal end of the main control module.

5. The audio converter amplifier output protection circuit according to claim 3, characterized in that: The second switch circuit includes a third relay and a fourth relay, One end of the third relay and the fourth relay is connected to the output end of the power amplifier module, A signal end of the third relay and a signal end of the fourth relay are respectively connected to a signal end of the main control module.

6. The audio converter amplifier output protection circuit according to claim 1, characterized in that: The virtual load module includes a first virtual load and a second virtual load. The input ends of the first virtual load and the second virtual load are respectively connected to the output end of the driving module. The second end of the first virtual load is connected to one end of an output end of the power amplifier module. The third end of the first virtual load is connected to the other end of an output end of the power amplifier module. The second end of the second virtual load is connected to one end of an output end of the power amplifier module. The third end of the second virtual load is connected to the other end of an output end of the power amplification module.

7. The audio converter amplifier output protection circuit according to claim 6, characterized in that: The driving module at least includes a first transistor and a second transistor. The base of the first transistor is connected to a signal output terminal of the main control module through a third resistor. The collector of the first transistor is connected to the input end of the first virtual load, The base of the second transistor is connected to a signal output terminal of the main control module through a fifth resistor. The collector of the second transistor is connected to the input end of the second virtual load. The emitters of the first transistor and the second transistor are connected to a common end.

8. The audio converter amplifier output protection circuit according to claim 7, characterized in that: The first transistor and the second transistor are selected as NPN transistors.

9. A protection method, characterized in that: include: Receive the audio signal output by the power amplifier module; Detecting a load signal at any output end of the power amplifier module, and outputting a control level according to the load signal; When the output end of the power amplifier module is not connected to a load, a high-level control signal is output to trigger the driving module to control the virtual load module to connect to the output end of the power amplifier module.

10. An electronic device, characterized in that: It has the function of implementing the protection method described in claim 9, and the function is implemented by hardware or by hardware executing corresponding software, and the hardware or the software includes one or more modules corresponding to the function.

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