Anti-clipping distortion circuit for high-power power amplifier

Abstract

The utility model discloses an anti-clipping distortion circuit for a high-power power amplifier. The anti-clipping distortion circuit comprises an output control module, a feedback module and a comparison module, the input end of the output control module is connected with an audio signal, and the output end is connected with a load; the input end of the feedback module is connected with a feedback signal; the first input end of the comparison module is connected with the output control module, the second input end is connected with the output end of the feedback module, and the output end is connected with the input end of the output control module; through the above structure, when the amplitude of an audio signal does not reach the maximum limit value, control is not started, and the audio signal directly passes through; and when the amplitude of the audio signal exceeds the set maximum value, the control is started, and the output state of the maximum limited amplitude value is kept, so that a power tube at a rear stage is prevented from being burnt out when the audio signal is in a large dynamic state.

Description

Technical Field

[0001] The utility model relates to the field of high-power power amplifiers, in particular to a high-power power amplifier anti-clipping distortion circuit. Background Art

[0002] At present, in high-power amplifiers such as stage amplifiers, KTV amplifiers, and cinema amplifiers, due to the high power, high current, and high voltage of the amplifiers, if they are not well controlled, it is easy to burn the speakers and damage the power transistors of the rear stage of the amplifier machine; and the sound is dynamic, especially when singing in KTV, everyone's voice is different, some people's voices are loud and loud, and the greater the dynamics of the sound, the easier it is to burn the speakers instantly; traditional high-power amplifiers are composed of pre-amplification and post-amplification. The voltage of the post-amplification will increase with the increase of power, and the current will also increase accordingly. If the input signal of the amplifier suddenly increases, if the post-amplification transistor cannot withstand it, it will burn the tube, or if it exceeds the power of the speaker, it will also burn the coil of the speaker; therefore, a high-power amplifier anti-clipping distortion circuit is urgently needed to solve the above problems. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model proposes a high-power amplifier anti-clipping distortion circuit.

[0004] An embodiment of the utility model solves the technical problem by adopting a technical solution: a high-power amplifier anti-clipping distortion circuit, comprising an output control module, a feedback module and a comparison module;

[0005] The input end of the output control module is connected to the audio signal, and the output end is connected to the load;

[0006] The input end of the feedback module is connected to the feedback signal;

[0007] The first input terminal of the comparison module is connected to the output control module, the second input terminal is connected to the output terminal of the feedback module, and the output terminal is connected to the input terminal of the output control module;

[0008] The audio signal that does not exceed the maximum limited amplitude value can be output through the output control module; the comparison module can reduce the amplitude of the audio signal input to the output control module when the audio signal exceeds the maximum limited amplitude value to maintain the maximum limited amplitude value for output.

[0009] As one of the preferred embodiments of the utility model, the output control module includes resistors R34-35, an operational amplifier IC3A, an operational amplifier IC4 and power tubes Q2-3, one end of the resistor R35 is connected to the audio signal, the other end of the resistor R35 is respectively connected to one end of the resistor R34, the positive phase input end of the operational amplifier IC3A and the output end of the comparison module, the other end of the resistor R34 is grounded, the inverting input end of the operational amplifier IC3A is respectively connected to the output end of the operational amplifier IC3A, the input end of the comparison module, the inverting input end of the operational amplifier IC4 and the ground end, the positive phase input end of the operational amplifier IC4 is respectively connected to the input end of the comparison module and the output end of the feedback module, the output end of the operational amplifier IC4 is respectively connected to the emitter of the power tube Q2 and the emitter of the power tube Q3, the collector of the power tube Q2 is connected to one end of the load, the collector of the power tube Q3 is connected to the other end of the load, the power supply end of the operational amplifier IC3A, the power supply end of the operational amplifier IC4, the base of the power tube Q2 and the base of the power tube Q3 are connected to the power supply.

[0010] As one of the preferred embodiments of the utility model, the feedback module includes an operational amplifier IC3B, a positive input terminal of the operational amplifier IC3B is connected to the feedback signal, and an inverting input terminal of the operational amplifier IC3B is respectively connected to the output control module, the comparison module, the output terminal of the operational amplifier IC3B and the ground terminal.

[0011] As one of the preferred embodiments of the utility model, a high-power power amplifier anti-clipping distortion circuit also includes resistors R25-27 and a capacitor C24, one end of the resistor R26 is respectively connected to the output end of the operational amplifier IC3B and one end of the capacitor C24, and the other end of the resistor R26 is respectively connected to the non-inverting input end of the operational amplifier IC3B and the other end of the capacitor C24 via the resistor R27 and the resistor R25.

[0012] As one of the preferred embodiments of the utility model, the comparison module includes an op amp IC1 B, an op amp IC1 A, a comparator IC2A, a comparator IC2B, a transistor Q1 and an optocoupler OPT 1, the non-inverting input terminal of the op amp IC1 B is connected to the output control module, the inverting input terminal is connected to the feedback module, the output terminal is respectively connected to the inverting input terminal of the comparator IC2A and the non-inverting input terminal of the comparator IC2B, the non-inverting input terminal of the comparator IC2A, the inverting input terminal of the comparator IC2B and the power supply terminal of the op amp IC1 A are connected to the power supply, the output terminal of the comparator IC2A and the output terminal of the comparator IC2B are respectively connected to the inverting input terminal of the op amp IC1 A, the output terminal of the op amp IC1 A, the base of the transistor Q1, the emitter of the transistor Q1 and the output terminal of the transistor Q1, the non-inverting input terminal of the op amp IC1 A is grounded, the collector of the transistor Q1 is connected to one end of the light emitter of the optocoupler OPT 1, and the optocoupler OPT The other end of the light emitter 1 is connected to the power supply, one end of the photocoupler OPT 1 light receiver is grounded, and the other end of the photocoupler OPT 1 light receiver is connected to the output control module.

[0013] As one of the preferred embodiments of the utility model, a high-power amplifier anti-clipping distortion circuit also includes a resistor R41, a resistor R42 and a capacitor C2 connected in series to the inverting input terminal of the operational amplifier IC 1B.

[0014] As one of the preferred embodiments of the utility model, a high-power amplifier anti-clipping distortion circuit also includes a resistor R1, a resistor R2 and a capacitor C1 connected in series to the non-inverting input terminal of an operational amplifier IC 1B.

[0015] The beneficial effects of the utility model include: a high-power power amplifier anti-clipping distortion circuit, comprising an output control module, a feedback module and a comparison module; the input end of the output control module is connected to an audio signal, and the output end is connected to a load; the input end of the feedback module is connected to a feedback signal; the first input end of the comparison module is connected to the output control module, the second input end is connected to the output end of the feedback module, and the output end is connected to the input end of the output control module; the audio signal that does not exceed the maximum limited amplitude value can be output through the output control module; the comparison module can reduce the amplitude of the audio signal input to the output control module when the audio signal exceeds the maximum limited amplitude value, so as to maintain the maximum limited amplitude value for output; through the above structure, when the amplitude of the audio signal does not reach the maximum limited value, the control can be stopped, and the audio signal can pass directly; when the amplitude of the audio signal exceeds the set maximum value, the control can be started, and the output state of the maximum limited amplitude value can be maintained, so as to avoid burning out the power tube of the subsequent stage when the audio signal has a large dynamic range. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0017] Figure 1 The circuit schematic diagram is a circuit diagram of a high-power amplifier anti-clipping distortion circuit;

[0018] Figure 2 It is the circuit schematic diagram of the first part of the output control module;

[0019] Figure 3 The second part of the circuit schematic diagram of the output control module;

[0020] Figure 4 It is the circuit schematic diagram of the feedback module;

[0021] Figure 5 This is the schematic diagram of the first part of the comparison module;

[0022] Figure 6 This is the schematic diagram of the second part of the comparison module;

[0023] Figure 7 This is the circuit schematic diagram of the third part of the comparison module. DETAILED DESCRIPTION

[0024] This section will describe in detail the specific embodiments of the utility model. The preferred embodiments of the utility model are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the utility model, but it cannot be understood as a limitation on the protection scope of the utility model.

[0025] In the description of the present utility model, the meaning of "more than" is more than two, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0026] In the description of the present invention, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do 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 on the present invention.

[0027] In the present invention, unless otherwise clearly defined, the words "set", "install", "connect" and the like should be understood in a broad sense, for example, they can be directly connected or indirectly connected through an intermediate medium; they can be fixedly connected or detachably connected or integrally formed; they can be mechanically connected; they can be the internal connection of two elements or the interaction relationship between two elements. Those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0028] Reference Figures 1 to 7 , a high-power amplifier anti-clipping distortion circuit, comprising an output control module 10, a feedback module 20 and a comparison module 30;

[0029] The input end of the output control module 10 is connected to the audio signal, and the output end is connected to the load;

[0030] The input end of the feedback module 20 receives the feedback signal;

[0031] The first input terminal of the comparison module 30 is connected to the output control module 10 , the second input terminal is connected to the output terminal of the feedback module 20 , and the output terminal is connected to the input terminal of the output control module 10 ;

[0032] The audio signal that does not exceed the maximum limited amplitude value can be output through the output control module 10; the comparison module 30 can reduce the amplitude of the audio signal input to the output control module 10 when the audio signal exceeds the maximum limited amplitude value to maintain the maximum limited amplitude value for output.

[0033] In the present utility model, the working principle is as follows: the audio signal of the front stage of the power amplifier reaches the positive input terminal of the operational amplifier IC3A after being divided by the resistors R35 and R34, the signal output by the operational amplifier IC3A passes through the capacitor C31 to the T+ terminal, and enters the operational amplifier IC4 for amplification, and the amplified signal is transmitted to the power tube Q2 and the power tube Q3, driving the power tube Q2 and the power tube Q3 to output; at the same time, the other path of the T+ terminal is input to the positive input terminal of the operational amplifier IC1B through the resistor R41, the resistor R42 and the capacitor C2 for positive end amplification, and the feedback signal of the power amplifier enters the T-terminal after being amplified by the operational amplifier IC3B, and the signal of the T-terminal enters the inverting input terminal of the operational amplifier IC1B after passing through the resistors R1, the resistor R2 and the capacitor C1 for negative end amplification. Since the positive and negative of the operational amplifier IC1B become high or low at the same time, the output is the midpoint voltage; when the audio signal is too large, the output of the power amplifier will be clipped, and the level fed back by the power amplifier will remain unchanged, that is, the level of the T-terminal remains unchanged, but the T The signal at the + end continues to increase, and the output level of the op amp IC1B becomes low. The output end of the op amp IC1B outputs a low level. The low level is input to the comparator IC2A and the comparator IC2B, so that the comparator IC2A and the comparator IC2B also output a low level, and is input to the inverting input end of the op amp IC1A through the resistor R11. The output of the op amp IC1A flips and then outputs a high level, which is output to the base of the transistor Q1 through the resistor R15. The transistor Q1 is turned on, and the LIM end becomes a low level, so that the optocoupler OPT1 is turned on. After the optocoupler OPT1 is turned on, the output is low resistance. The internal resistance of the optocoupler OPT1 becomes 100 ohms. After the voltage is divided by the resistor R35, the input amplitude is reduced until the output is not clipped and distorted. Through the above structure, the control can be stopped when the amplitude of the audio signal does not reach the maximum limit value, and the audio signal passes directly; the control is started when the amplitude of the audio signal exceeds the set maximum value, and the output state of the maximum limit amplitude value is maintained to avoid burning out the power tube of the subsequent stage when the audio signal is dynamic.

[0034] As a preferred embodiment of the output control module 10, the output control module 10 includes resistors R34-35, an operational amplifier IC3A, an operational amplifier IC4 and power tubes Q2-3, one end of the resistor R35 is connected to the audio signal, the other end of the resistor R35 is respectively connected to one end of the resistor R34, the positive phase input end of the operational amplifier IC3A and the output end of the comparison module 30, the other end of the resistor R34 is grounded, the inverting input end of the operational amplifier IC3A is respectively connected to the output end of the operational amplifier IC3A, the input end of the comparison module 30 and the inverting input end of the operational amplifier IC4 and the ground end, the positive phase input end of the operational amplifier IC4 is respectively connected to the input end of the comparison module 30 and the output end of the feedback module 20, the output end of the operational amplifier IC4 is respectively connected to the emitter of the power tube Q2 and the emitter of the power tube Q3, the collector of the power tube Q2 is connected to one end of the load, the collector of the power tube Q3 is connected to the other end of the load, the power supply end of the operational amplifier IC3A, the operational amplifier I The power supply end of C4, the base of the power tube Q2 and the base of the power tube Q3 are connected to the power supply.

[0035] As a preferred embodiment of the feedback module 20, the feedback module 20 includes an operational amplifier IC3B, a positive input terminal of the operational amplifier IC3B is connected to the feedback signal, and an inverting input terminal of the operational amplifier IC3B is respectively connected to the output control module 10, the comparison module 30, the output terminal of the operational amplifier IC3B and the ground terminal.

[0036] A high-power amplifier anti-clipping distortion circuit also includes resistors R25-27 and a capacitor C24, one end of the resistor R26 is respectively connected to the output end of the operational amplifier IC3B and one end of the capacitor C24, and the other end of the resistor R26 is respectively connected to the non-inverting input end of the operational amplifier IC3B and the other end of the capacitor C24 via the resistor R27 and the resistor R25.

[0037] As a preferred embodiment of the comparison module 30, the comparison module 30 includes an operational amplifier IC1B, an operational amplifier IC1A, a comparator IC2A, a comparator IC2B, a transistor Q1 and an optocoupler OPT1, the non-inverting input terminal of the operational amplifier IC1B is connected to the output control module 10, the inverting input terminal is connected to the feedback module 20, the output terminal is respectively connected to the inverting input terminal of the comparator IC2A and the non-inverting input terminal of the comparator IC2B, the non-inverting input terminal of the comparator IC2A, the inverting input terminal of the comparator IC2B and the power supply terminal of the operational amplifier IC1A are connected to the power supply, the output terminal of the comparator IC2A and the output terminal of the comparator IC2B are respectively connected to the inverting input terminal of the operational amplifier IC1A, the output terminal of the operational amplifier IC1A, the base of the transistor Q1, the emitter of the transistor Q1 and the output terminal of the operational amplifier IC1B. The positive input terminal of A is grounded, the collector of transistor Q1 is connected to one end of the optocoupler OPT1 light emitter, the other end of the optocoupler OPT 1 light emitter is connected to the power supply, one end of the optocoupler OPT 1 light receiver is grounded, and the other end of the optocoupler OPT 1 light receiver is connected to the output control module 10.

[0038] A high-power amplifier anti-clipping distortion circuit also includes a resistor R41, a resistor R42 and a capacitor C2 connected in series to the inverting input terminal of an operational amplifier IC1B.

[0039] A high-power amplifier anti-clipping distortion circuit also includes a resistor R1, a resistor R2 and a capacitor C1 which are serially connected to the non-phase input terminal of an operational amplifier IC1B.

[0040] Of course, the present invention is not limited to the above-mentioned embodiments, and technicians familiar with the field may make equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications and substitutions are all included in the scope defined by the claims of this application.

Claims

1. A high-power amplifier anti-clipping distortion circuit, characterized in that: It comprises an output control module (10), a feedback module (20) and a comparison module (30); The input end of the output control module (10) is connected to an audio signal, and the output end is connected to a load; The input end of the feedback module (20) is connected to the feedback signal; The first input end of the comparison module (30) is connected to the output control module (10), the second input end is connected to the output end of the feedback module (20), and the output end is connected to the input end of the output control module (10); An audio signal that does not exceed the maximum limited amplitude value can be output via the output control module (10); and the comparison module (30) can reduce the amplitude of the audio signal input to the output control module (10) when the audio signal exceeds the maximum limited amplitude value, so as to maintain the maximum limited amplitude value for output.

2. The high-power amplifier anti-clipping distortion circuit according to claim 1, characterized in that: The output control module (10) comprises resistors R34-35, an operational amplifier IC3A, an operational amplifier IC4 and power tubes Q2-3, one end of the resistor R35 is connected to the audio signal, the other end of the resistor R35 is respectively connected to one end of the resistor R34, the positive phase input end of the operational amplifier IC3A and the output end of the comparison module (30), the other end of the resistor R34 is grounded, the negative phase input end of the operational amplifier IC3A is respectively connected to the output end of the operational amplifier IC3A, the input end of the comparison module (30) and the negative phase input end of the operational amplifier IC4 and the ground end, the positive phase input end of the operational amplifier IC4 is respectively connected to the input end of the comparison module (30) and the output end of the feedback module (20), the output end of the operational amplifier IC4 is respectively connected to the emitter of the power tube Q2 and the emitter of the power tube Q3, the collector of the power tube Q2 is connected to one end of the load, the collector of the power tube Q3 is connected to the other end of the load, the power supply end of the operational amplifier IC3A, the operational amplifier I The power supply end of C4, the base of the power tube Q2 and the base of the power tube Q3 are connected to the power supply.

3. The high-power amplifier anti-clipping distortion circuit according to claim 1, characterized in that: The feedback module (20) comprises an operational amplifier IC3B, a positive input terminal of the operational amplifier IC3B is connected to a feedback signal, and an inverting input terminal of the operational amplifier IC3B is respectively connected to the output control module (10), the comparison module (30), the output terminal of the operational amplifier IC3B and a ground terminal.

4. The high-power amplifier anti-clipping distortion circuit according to claim 3, characterized in that: It also includes resistors R25-27 and a capacitor C24, one end of the resistor R26 is connected to the output end of the operational amplifier IC3B and one end of the capacitor C24 respectively, and the other end of the resistor R26 is connected to the non-inverting input end of the operational amplifier IC3B and the other end of the capacitor C24 respectively through the resistor R27 and the resistor R25.

5. The high-power amplifier anti-clipping distortion circuit according to claim 1, characterized in that: The comparison module (30) comprises an operational amplifier IC1B, an operational amplifier IC1A, a comparator IC2A, a comparator IC2B, a transistor Q1 and an optocoupler OPT1, wherein the positive phase input terminal of the operational amplifier IC1B is connected to the output control module (10), the negative phase input terminal is connected to the feedback module (20), the output terminal is respectively connected to the negative phase input terminal of the comparator IC2A and the positive phase input terminal of the comparator IC2B, the positive phase input terminal of the comparator IC2A, the negative phase input terminal of the comparator IC2B and the power supply terminal of the operational amplifier IC1A are connected to the power supply, the output terminal of the comparator IC2A and the output terminal of the comparator IC2B are respectively connected to the negative phase input terminal of the operational amplifier IC1A, the output terminal of the operational amplifier IC1A, the base of the transistor Q1, the emitter of the transistor Q1 and the positive phase input terminal of the operational amplifier IC1A are grounded, the collector of the transistor Q1 is connected to one end of the light emitter of the optocoupler OPT1, and the optocoupler OPT1 is connected to the positive phase input terminal of the operational amplifier IC1A. The other end of the light emitter 1 is connected to a power source, one end of the optical coupler OPT 1 light receiver is grounded, and the other end of the optical coupler OPT 1 light receiver is connected to the output control module (10).

6. The high-power amplifier anti-clipping distortion circuit according to claim 5, characterized in that: The circuit also includes a resistor R41, a resistor R42 and a capacitor C2 which are serially connected to the inverting input terminal of the operational amplifier IC1B.

7. The high-power amplifier anti-clipping distortion circuit according to claim 5, characterized in that: The circuit also includes a resistor R1, a resistor R2 and a capacitor C1 which are serially connected to the non-inverting input terminal of the operational amplifier IC1 B.

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