Small audio signal detection control circuit

Abstract

A small audio signal detection control circuit is characterized in that a power supply module is connected with a signal amplification circuit, a threshold detection circuit, a filter rectification circuit and a main control module and supplies power to the signal amplification circuit, the threshold detection circuit, the filter rectification circuit and the main control module, and a signal source is connected with the signal amplification circuit and provides signals for the signal amplification circuit; the main control module is connected with a threshold detection circuit and a filter rectification circuit, and the threshold detection circuit detects a signal passing through the signal amplification circuit; and the filtering and rectifying circuit processes the signal before entering the main control module. According to the audio small signal detection control circuit, when a signal source has no signal output for a long time and only system bottom noise exists, the detection circuit outputs a high level to the main control module, and the main control module controls to cut off a power supply except the detection circuit and enters a standby or shutdown mode; when a signal is input, the detection circuit outputs a low level to the main control module, and the main control module controls the detection circuit to work again. Energy waste and product service life reduction caused by long-time non-use of equipment can be effectively prevented, and the automation degree of the circuit is improved.

Description

Technical Field

[0001] The utility model application relates to the technical field related to signal detection, and in particular to an audio small signal detection control circuit. Background Art

[0002] In the prior art, audio playback devices often require manual control of their power supply via switches, buttons, or remote controls to switch them into standby or active mode. If forgotten, the device remains in active mode. This wastes energy for battery-powered audio devices, shortens their lifespan, and lacks intelligent functionality.

[0003] Alternatively, a timer can be used to set a predetermined time period. If no audio signal is detected within the time period, the device will enter a standby or shutdown state. Using a timer can easily lead to unnecessary power switching, affecting the user experience.

[0004] The above methods have great limitations and cannot meet the needs in some scenarios with a wide range of applications, and also cause some unnecessary waste and loss of audio equipment. Summary of the Invention

[0005] In order to overcome the problems existing in the related art, the present utility model application provides an audio small signal detection control circuit, which can automatically detect and make a judgment when there is no audio signal input for a long time, and at the same time control it to enter the standby or shutdown state; when there is an audio signal input, it automatically enters the working state without manual intervention, which greatly improves the automation level and application scope of the circuit.

[0006] The utility model application provides an audio small signal detection control circuit, including: a signal source, a signal amplifying circuit, a threshold detection circuit, a filtering and rectifying circuit, a power supply module, and a main control module; the power supply module is electrically connected to the signal amplifying circuit, the threshold detection circuit, the filtering and rectifying circuit, and the main control module and supplies power to them, the signal source is connected to the signal amplifying circuit and provides a signal to the signal amplifying circuit; the main control module is connected to the threshold detection circuit and the filtering and rectifying circuit, the threshold detection circuit detects the signal amplified by the signal amplifying circuit; the filtering and rectifying circuit processes the signal before entering the main control module.

[0007] In the above-mentioned audio small signal detection control circuit, the signal amplification circuit is provided with a resistor R1, a resistor R2, a capacitor C1, and an operational amplifier U1A. The non-inverting input terminal of the operational amplifier is grounded, and the inverting input terminal is connected to the resistor R1. The operational amplifier U1A is connected in parallel with the resistor R2 and the capacitor C1.

[0008] In the above-mentioned audio small signal detection control circuit, the threshold detection circuit is provided with a resistor R3, a resistor R4, a resistor R5, and a transistor Q1. The base of the transistor Q1 is connected in series with the resistor R3 and in parallel with the resistor R4. One end of the resistor R4 is connected to the base of the transistor Q1, and the other end is connected to the emitter of the transistor Q1; the collector of the transistor Q1 is connected in series with the resistor R5.

[0009] In the above-mentioned audio small signal detection and control circuit, the filtering and rectifying circuit is provided with a capacitor C2 , one end of the capacitor C2 is connected to the emitter of the transistor Q1 , and the other end is connected to the collector of the transistor Q1 .

[0010] In the above-mentioned audio small signal detection control circuit, the capacitor C2 and the transistor Q1 are connected in parallel to the port IO1, and the port IO1 is connected to the system MCU. The port IO1 and the system MCU form the main control module for detecting the output level state of the filter and rectifier circuit.

[0011] In the above-mentioned audio small signal detection control circuit, the power supply module is provided with power supply VCC, power supply VSS, and power supply VDD, which are used to power the main control module, the signal amplification circuit, the threshold detection circuit, and the filter rectifier circuit, and the power supply is still maintained when entering the standby state.

[0012] In the above-mentioned audio small signal detection control circuit, the resistor R3 and the resistor R4 are adjustable resistors.

[0013] The technical solution provided by this utility model application can have the following beneficial effects: When the signal source has no signal output for a long time and only system background noise is present, the detection circuit outputs a high level to the main control module, which controls the main control module to cut off the power supply except for the detection circuit and enter standby or shutdown mode; when a signal is input, the detection circuit outputs a low level to the main control module, which controls it to resume operation. This can effectively prevent energy waste and shorten product life when the device is not used for a long time, and improve the degree of circuit automation.

[0014] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory and are not intended to limit the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and other purposes, features and advantages of the present invention will become more apparent by describing in more detail the exemplary embodiments of the present invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the present invention.

[0016] Figure 1 This is a structural diagram of an audio small signal detection control circuit shown in an embodiment of the present utility model application;

[0017] Figure 2 This is a schematic diagram of an audio small signal detection control circuit shown in an embodiment of the present utility model application. DETAILED DESCRIPTION

[0018] The following describes preferred embodiments of the present invention in more detail with reference to the accompanying drawings. Although the accompanying drawings illustrate preferred embodiments of the present invention, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. Rather, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0019] The terms used in this utility model application are for the purpose of describing specific embodiments only and are not intended to limit this utility model application. The singular forms "a," "the," and "the" used in this utility model application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0020] It should be understood that although the terms "first", "second", "third", etc. may be used to describe various information in this utility model application, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of this utility model application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this utility model application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0021] The technical solutions of the embodiments of the present utility model are described in detail below with reference to the accompanying drawings.

[0022] In the prior art, most audio playback devices require manual control of the device power state to control the system standby and on / off states. If you forget to turn off the device after use, the machine will remain in the working state, which will cause some unnecessary waste and loss to the audio device. By adding a detection circuit, this detection circuit can automatically detect and judge the result even when there is no audio signal input for a long time, and then control it to enter the standby or off state according to the result. When there is an audio signal input, it automatically enters the working state. No human intervention is required, which greatly improves the circuit's degree of automation and application scope. At the same time, the circuit cost is low. In practical applications, the circuit can be easily added to the system design. It is a circuit that can be widely used in various audio devices.

[0023] Figure 1 It is a structural diagram of an audio small signal detection control circuit shown in an embodiment of the present utility model application.

[0024] See also Figure 1 An audio small signal detection and control circuit includes: a signal source, a signal amplification circuit, a threshold detection circuit, a filter and rectifier circuit, a power supply module, and a main control module. The power supply module is electrically connected to the signal amplification circuit, the threshold detection circuit, the filter and rectifier circuit, and the main control module to supply power to them. The signal source is connected to the signal amplification circuit and provides a signal to the signal amplification circuit. The main control module is connected to the threshold detection circuit and the filter and rectifier circuit. The threshold detection circuit detects the signal amplified by the signal amplification circuit. The filter and rectifier circuit processes the signal before entering the main control module.

[0025] This audio small signal detection circuit can convert manual control into automatic control, improve the automation level of the circuit, and reduce energy waste and loss of audio equipment; at the same time, its hardware cost is low and it can be easily added to the system design, greatly enhancing the application range of the circuit.

[0026] Figure 2 This is a schematic diagram of an audio small signal detection control circuit shown in an embodiment of the present utility model application.

[0027] See also Figure 2 The signal source V1 is used to provide an audio signal, connected to the signal amplifying circuit, and provide a system judgment source.

[0028] See also Figure 2The signal amplification circuit includes resistors R1 and R2, capacitor C1, and an operational amplifier U1A. The operational amplifier has a non-inverting input connected to ground and an inverting input connected to resistor R1. The operational amplifier U1A is connected in parallel with resistor R2 and capacitor C1. The signal amplification circuit is configured to amplify a signal input from a signal source V1, causing the signal to reach a detection threshold and isolating the signal from interfering with the signal source.

[0029] See also Figure 2 The threshold detection circuit comprises resistors R3, R4, and R5, and a transistor Q1. The base of transistor Q1 is connected in series with resistor R3 and in parallel with resistor R4. One end of resistor R4 is connected to the base of transistor Q1, and the other end is connected to the emitter of transistor Q1. The collector of transistor Q1 is connected in series with resistor R5. The threshold detection circuit is used to determine the magnitude threshold of the amplified signal.

[0030] See also Figure 2 The filter and rectifier circuit is provided with a capacitor C2, one end of which is connected to the emitter of the transistor Q1, and the other end is connected to the collector of the transistor Q1. The filter and rectifier circuit is used to filter and rectify the AC or switching signal and output a stable DC signal.

[0031] See also Figure 2 The capacitor C2 and the transistor Q1 are connected in parallel to a port IO1, which is connected to the system MCU. The port IO1 and the system MCU form the main control module for detecting the output level of the filter and rectifier circuit. The main control module controls the operating state of the entire system based on the output level of the filter and rectifier circuit.

[0032] See also Figure 2 The power supply module is provided with a power supply VCC, a power supply VSS, and a power supply VDD, which are used to supply power to the main control module, the signal amplification circuit, the threshold detection circuit, and the filter rectifier circuit, and maintains power supply when entering the standby state.

[0033] See also Figure 2 The resistor R3 and the resistor R4 are adjustable resistors. By changing the amplification factor of the signal amplification circuit and the resistance values ​​of the resistor R3 and the resistor R4, the threshold value of the detection circuit can be changed.

[0034] See also Figure 1 and Figure 2In this audio small signal detection circuit, the signal source V1 provides an audio signal. After the audio input signal passes through the signal amplification circuit, it reaches the threshold detection circuit. When the audio input signal is less than the threshold, the IO1 port outputs a high level. After the main control module where the MCU is located detects the high level for a long time, it controls the power supply except for the detection circuit to cut off, so that the entire system enters standby or shutdown mode. When the audio input signal is greater than the threshold, the IO1 port outputs a low level. After the main control module where the MCU is located detects the low level, it controls the entire system to restart operation. The power module supplies power to the main control module, the signal amplification circuit, the threshold detection circuit, and the filter and rectifier circuit, so that they enter normal working state.

[0035] See also Figure 1 and Figure 2 This audio low-signal detection and control circuit, when the signal source is silent for an extended period, outputs a high level to the main control module. The main control module then shuts off all power except for the detection circuit and enters standby or shutdown mode. Upon signal input, the detection circuit outputs a low level to the main control module, resuming operation. This effectively prevents energy waste and shortened product lifespan caused by prolonged non-use. While improving the circuit's automation level, its low hardware cost makes it widely applicable to various audio devices.

[0036] The above descriptions of various embodiments of the present invention are intended to be illustrative, non-exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or improvements to existing technologies, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. An audio small signal detection control circuit, characterized in that: include: Signal source, signal amplification circuit, threshold detection circuit, filter and rectifier circuit, power supply module, main control module; The power supply module is electrically connected to the signal amplifying circuit, the threshold detection circuit, the filtering and rectifying circuit, and the main control module and supplies power to them. The signal source is connected to the signal amplifying circuit and provides a signal to the signal amplifying circuit. The main control module is connected to the threshold detection circuit and the filtering and rectifying circuit. The threshold detection circuit detects the signal amplified by the signal amplifying circuit. The filtering and rectifying circuit processes the signal before entering the main control module.

2. The audio small signal detection control circuit according to claim 1, characterized in that: The signal amplification circuit includes a resistor R1, a resistor R2, a capacitor C1, and an operational amplifier U1A. The non-inverting input terminal of the operational amplifier is grounded, and the inverting input terminal is connected to the resistor R1. The operational amplifier U1A is connected in parallel with the resistor R2 and the capacitor C1.

3. The audio small signal detection control circuit according to claim 2, characterized in that: The threshold detection circuit is provided with a resistor R3, a resistor R4, a resistor R5, and a transistor Q1. The base of the transistor Q1 is connected in series with the resistor R3 and in parallel with the resistor R4. One end of the resistor R4 is connected to the base of the transistor Q1, and the other end is connected to the emitter of the transistor Q1. The collector of the transistor Q1 is connected in series with the resistor R5.

4. The audio small signal detection control circuit according to claim 3, characterized in that: The filtering and rectifying circuit is provided with a capacitor C2 , one end of the capacitor C2 is connected to the emitter of the transistor Q1 , and the other end of the capacitor C2 is connected to the collector of the transistor Q1 .

5. The audio small signal detection control circuit according to claim 4, characterized in that: The capacitor C2 and the transistor Q1 are connected in parallel to a port IO1 , and the port IO1 is connected to a system MCU. The port IO1 and the system MCU form the main control module for detecting the output level state of the filter and rectifier circuit.

6. The audio small signal detection control circuit according to claim 5, characterized in that: The power supply module is provided with power supply VCC, power supply VSS and power supply VDD, which are used to supply power to the main control module, the signal amplifying circuit, the threshold detection circuit and the filtering and rectifying circuit, and maintains power supply when entering the standby state.

7. The audio small signal detection control circuit according to claim 6, characterized in that: The resistor R3 and the resistor R4 are adjustable resistors.

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