CN218633868U

CN218633868U - Voltage self-adaptive audio power amplifier

Info

Publication number: CN218633868U
Application number: CN202223037198.XU
Authority: CN
Inventors: 钟志宏; 任学敏; 粟柱锦
Original assignee: Fiio Electronics Technology Co ltd
Current assignee: Fiio Electronics Technology Co ltd
Priority date: 2022-11-15
Filing date: 2022-11-15
Publication date: 2023-03-14
Anticipated expiration: 2032-11-15

Abstract

The utility model discloses a voltage self-adaptation's audio power amplifier, including amplifier one, amplifier two and detection control circuit, the power supply end of amplifier two is connected with the power supply positive pole, the earthing terminal of amplifier two is connected with the power supply negative pole, detection control circuit includes the MCU chip, voltage sampling detection module and variable resistance, voltage sampling detection module's sample end passes through the wire and is connected with the power supply positive pole, voltage sampling detection module passes through the wire with the MCU chip and is connected, variable resistance's sliding end passes through the wire with the MCU chip and is connected, amplifier one is gone up and is provided with negative input end one, amplifier one is gone up and is provided with positive input end one. The utility model discloses detection control circuit can real-time detection supply voltage's change, according to supply voltage's height, controls variable resistance R1 to change preceding stage amplifier circuit's gain, make the biggest undistorted power of power amplifier, change that can adapt to supply voltage automatically, in order to obtain the biggest undistorted power.

Description

Voltage self-adaptive audio power amplifier

Technical Field

The utility model relates to an audio power amplifier technical field, specifically speaking relates to a voltage self-adaptation's audio power amplifier.

Background

The operating voltage of present audio power amplifiers is fixed. The fixed supply voltage determines the maximum undistorted voltage output of the power amplifier. If the supply voltage varies, the maximum undistorted voltage will also follow the variation.

Chinese patent No. CN215345040U provides an audio power amplifier, including an audio power amplifier, a power amplifying unit, a protection unit and a decoding unit are disposed in the audio power amplifier, a positive wiring terminal and a negative wiring terminal are disposed on the rear side of the audio power amplifier, and the power amplifying unit, the decoding unit, the positive wiring terminal and the negative wiring terminal form a working circuit through connection wires; the protection unit is connected to the working circuit through a connecting wire; a decoding unit is arranged to decode the audio, so that the audio after passing through the audio power amplifier can be directly played in a loudspeaker or a sound box, and the wiring disorder caused by an external decoder is avoided; the protection unit is arranged to avoid the damage of high-frequency and high-power audio frequency to the interior of the audio power amplifier through the physical disconnection of the fuse; has the functions of simplifying operation and ensuring safety.

The voltage gain of current power amplifiers is fixed. The output voltage clipping may be distorted when the voltage drops, which may result in a maximum volume. When the voltage rises, a higher supply voltage cannot be fully utilized.

SUMMERY OF THE UTILITY MODEL

Technical problem to be solved

In view of the deficiencies of the prior art, it is an object of the present invention to provide an audio power amplifier with voltage adaptation.

(II) technical scheme

According to the technical scheme, the audio power amplifier comprises a first amplifier, a second amplifier and a detection control circuit, the power supply end of the second amplifier is connected with a power supply anode, the grounding end of the second amplifier is connected with a power supply cathode, the detection control circuit comprises an MCU chip, a voltage sampling detection module and a variable resistor, the sampling end of the voltage sampling detection module is connected with the power supply anode through a wire, the voltage sampling detection module is connected with the MCU chip through a wire, and the sliding end of the variable resistor is connected with the MCU chip through a wire.

Preferably, the first amplifier is provided with a first negative input end, and the first amplifier is provided with a first positive input end.

Preferably, the first negative input end is connected with a first resistor through a conducting wire, and the first negative input end is connected with the signal input end through a conducting wire.

Preferably, the first positive input end is connected to a second resistor through a conductive wire, and the first positive input end is connected to one fixed end of the variable resistor through a conductive wire.

Preferably, the second amplifier is provided with a second negative input end, and the second amplifier is provided with a second positive input end.

Preferably, the negative input end two-way is communicated with a bias voltage through a conductive wire, the positive input end two-way is communicated with one end of the first amplifier through a conductive wire, and the positive input end two-way is connected with the other fixed end of the variable resistor through a conductive wire.

And as a preferred scheme, the MCU chip is provided with a GPIO I and a GPIO II, and the GPIO I and the GPIO II are respectively connected with the sliding end of the variable resistor and the output end of the voltage sampling detection module.

(III) advantageous effects

Compared with the prior art, the utility model provides a voltage self-adaptation's audio power amplifier possesses following beneficial effect:

1. the circuit detects the change of the power supply voltage in real time, and controls the variable resistor according to the height of the power supply voltage, so that the gain of the preceding stage amplifying circuit is changed, the maximum undistorted power of the power amplifier can be automatically adapted to the change of the power supply voltage, and the maximum undistorted power can be obtained.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

fig. 2 is the schematic diagram of the structure of the detection control circuit of the present invention.

In the figure: 1. a first amplifier; 2. a second amplifier; 3. a detection control circuit; 4. a negative input end I; 5. a first positive input end; 6. a first resistor; 7. a second resistor; 8. a negative input end II; 9. a positive input end II; 10. a power supply positive electrode; 11. a power supply cathode; 12. an MCU chip; 13. GPIO one; 14. GPIO two; 15. a voltage sampling detection module; 16. a variable resistance.

Detailed Description

The invention will be further elucidated and described with reference to the following embodiments and drawings in which:

referring to fig. 1-2, the present invention: the power amplifier comprises an amplifier I1, an amplifier II 2 and a detection control circuit 3, wherein a power supply end of the amplifier II 2 is connected with a power supply anode 10, a grounding end of the amplifier II 2 is connected with a power supply cathode 11, the detection control circuit 3 comprises an MCU chip 12, a voltage sampling detection module 15 and a variable resistor 16, a sampling end of the voltage sampling detection module 15 is connected with the power supply anode 10 through a lead, the voltage sampling detection module 15 is connected with the MCU chip 12 through a lead, a sliding end of the variable resistor 16 is connected with the MCU chip 12 through a lead, the MCU chip 12 is provided with a GPIO I13 and a GPIO II 14, the GPIO I13 and the GPIO II 14 are respectively connected with the sliding end of the variable resistor 16 and an output end of the voltage sampling detection module 15, the circuit detects the change of the voltage VCC of the power supply anode 10 in real time, and controls the variable resistor 16 according to the height of the voltage VCC of the power supply anode 10, thereby changing the gain of a pre-stage amplification circuit, enabling the maximum undistorted power of the power amplifier to be automatically adapted to the change of the voltage VCC of the power supply anode 10, and obtaining the maximum undistorted power.

Preferably, the amplifier 1 is provided with a negative input end one 4 and a positive input end one 5, the negative input end one 4 is connected with a resistor one 6 through a conductive wire, the negative input end one 4 is connected with the signal input end through a conductive wire, the positive input end one 5 is connected with a resistor two 7 through a conductive wire, one end of the resistor two 7 is grounded, and the positive input end one 5 is connected with one fixed end of the variable resistor 16 through a conductive wire.

Preferably, the second amplifier 2 is provided with a second negative input end 8 and a second positive input end 9, the second negative input end 8 is communicated with the bias voltage through a conductive wire, one end of the second amplifier 2 is a signal output end, the second positive input end 9 is communicated with one end of the first amplifier 1 through a conductive wire, and the second positive input end 9 is connected with the other fixed end of the variable resistor 16 through a conductive wire.

The utility model discloses a theory of operation is: this scheme has increased a detection control circuit 3: the power supply positive electrode 10 voltage VCC detection of the power amplifier → MCU chip 12 receiving → MCU chip 12 voltage analysis → GPIO two 14 output control signal through MCU chip 10 → control variable resistor 16 adjustment, the circuit detects the variation of the power supply positive electrode 10 voltage VCC in real time, and controls variable resistor 16 according to the height of the power supply positive electrode 10 voltage VCC, thereby changing the gain of the preceding stage amplifying circuit, making the maximum undistorted power of the power amplifier, automatically adapting to the variation of the power supply positive electrode 10 voltage VCC, and obtaining the maximum undistorted power.

It should be finally noted that the above embodiments are only intended to illustrate the technical solutions of the present invention, and not to limit the scope of the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present invention can be modified or replaced with equivalents without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A voltage adaptive audio power amplifier comprising a first amplifier (1), a second amplifier (2) and a detection control circuit (3), characterized by: the power supply end of the second amplifier (2) is connected with a power supply anode (10), the grounding end of the second amplifier (2) is connected with a power supply cathode (11), the detection control circuit (3) comprises an MCU chip (12), a voltage sampling detection module (15) and a variable resistor (16), the sampling end of the voltage sampling detection module (15) is connected with the power supply anode (10) through a wire, the voltage sampling detection module (15) is connected with the MCU chip (12) through a wire, and the sliding end of the variable resistor (16) is connected with the MCU chip (12) through a wire.

2. A voltage adaptive audio power amplifier as defined in claim 1, wherein: the amplifier I (1) is provided with a negative input end I (4), and the amplifier I (1) is provided with a positive input end I (5).

3. A voltage adaptive audio power amplifier as defined in claim 2, wherein: the first negative input end (4) is connected with a first resistor (6) through a conducting wire, and the first negative input end (4) is connected with the signal input end through a conducting wire.

4. A voltage adaptive audio power amplifier as defined in claim 2, wherein: the positive input end I (5) is connected with a resistor II (7) through a conducting wire, one end of the resistor II (7) is grounded, and the positive input end I (5) is connected with one fixed end of the variable resistor (16) through a conducting wire.

5. A voltage adaptive audio power amplifier as defined in claim 1, wherein: the amplifier II (2) is provided with a negative input end II (8), one end of the amplifier II (2) is a signal output end, and the amplifier II (2) is provided with a positive input end II (9).

6. A voltage adaptive audio power amplifier as defined in claim 5, wherein: the negative input end II (8) is communicated with bias voltage through a conducting wire, the positive input end II (9) is communicated with one end of the amplifier I (1) through a conducting wire, and the positive input end II (9) is connected with the other fixed end of the variable resistor (16) through a conducting wire.

7. A voltage adaptive audio power amplifier as defined in claim 1, wherein: the MCU chip (12) is provided with a GPIO I (13) and a GPIO II (14), and the GPIO I (13) and the GPIO II (14) are respectively connected with the sliding end of the variable resistor (16) and the output end of the voltage sampling detection module (15).