A power amplifier self-boosting control circuit capable of reducing delay

Abstract

This utility model discloses a power amplifier self-boost control circuit that can reduce latency, including an AC-DC module, a first filter module, a switching module, a buck module, a boost module, a second filter module, a DSP module, and a power amplifier module. The AC-DC module is connected to the AC power supply, the first filter module, the switching module, and the buck module. The boost module is connected to the buck module, the power amplifier module, and the battery. The DSP module is connected to the buck module and the power amplifier module. The switching module is connected to the power amplifier module. The power amplifier module is connected to the speaker. Through the above circuit, the first filter module acts as a large capacitor for filtering when powered by AC, and the second filter module acts as a small capacitor for filtering when powered by battery self-boost, thereby solving the boost latency problem without increasing the battery capacity.

Description

Technical Field

[0001] This utility model relates to the field of audio, and in particular to a power amplifier self-boost control circuit that can reduce delay. Background Technology

[0002] An adaptive boost amplifier circuit detects the level of the input music signal and then controls the output voltage of the boost circuit according to the amplitude of the signal, so that the power supply voltage of the amplifier changes with the level of the music. Adaptive boost circuits are widely used in audio products with built-in battery boost circuits due to their energy saving.

[0003] When the power amplifier's power supply pins are working, they generate some pulse interference that is conducted to the preamplifier circuit. Often, a large capacitor needs to be added to the power supply pins to filter out these interference pulses. However, large filter capacitors typically require a charging time of 2-5 milliseconds. This means that when the amplifier increases the music volume, the time it takes for the boost circuit to increase the voltage to the high-voltage output is 2-5 milliseconds. If the voltage and music are out of sync, distortion will occur. Amplifiers usually delay the sound by a corresponding amount of time to avoid distortion, but this delay issue still exists. The usual solution is to eliminate the boost circuit and directly fix the maximum voltage of the power amplifier. This has little impact on AC-powered machines, but for battery-powered machines, the battery capacity needs to be increased to improve playback time.

[0004] Therefore, there is an urgent need for a power amplifier self-boost control circuit that can reduce delay to solve the above problems. Utility Model Content

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a power amplifier self-boost control circuit that can reduce delay.

[0006] The technical solution adopted by one embodiment of this utility model to solve its technical problem is: a power amplifier self-boost control circuit that can reduce delay, including an AC-DC module, a first filter module, a switching module, a buck module, a boost module, a second filter module, a DSP module, and a power amplifier module;

[0007] The AC-DC module is connected to the AC power supply, the first filter module, the switching module, and the step-down module, respectively.

[0008] The boost module is connected to the buck module, the power amplifier module, and the battery, respectively.

[0009] The DSP module is connected to both the buck module and the power amplifier module.

[0010] The switch module is connected to the power amplifier module;

[0011] The amplifier module is connected to the speaker.

[0012] As one of the preferred embodiments of this utility model, the first filter module includes capacitors CE3, C3 and CB5 connected in parallel. One end of the parallel connection is connected to the AC-DC module, the switching module and the step-down module respectively, and the other end of the parallel connection is connected to the ground terminal.

[0013] In one preferred embodiment of this utility model, the switching module includes resistors R3-R6, MOSFET Q2, and transistor Q3. One end of resistor R3 is connected to one end of resistor R5, the drain of MOSFET Q2, the first filter module, and the switching module. The other end of resistor R3 is connected to the gate of MOSFET Q2 and one end of resistor R4. The other end of resistor R4 is connected to the collector of transistor Q3. The base of transistor Q3 is connected to the other ends of resistor R5 and resistor R6. The other end of resistor R6 and the emitter of transistor Q3 are connected to ground. The source of MOSFET Q2 is connected to the power amplifier module.

[0014] As one of the preferred embodiments of this utility model, the second filter module includes capacitors C25, C28, C29 and C30 connected in parallel. One end of the parallel connection is connected to the boost module and the power amplifier module respectively, and the other end of the parallel connection is connected to the ground terminal.

[0015] As one of the preferred embodiments of this utility model, a power amplifier self-boost control circuit that can reduce delay also includes a unidirectional conduction module connected between the first filter module, the switching module, the buck module and the boost module.

[0016] As one of the preferred embodiments of this utility model, the unidirectional conduction module includes diode D1 and diode D2. The anode of diode D1 is connected to the first filter module and the switch module respectively, the cathode of diode D1 is connected to the buck module and the cathode of diode D2 respectively, and the anode of diode D2 is connected to the boost module.

[0017] The beneficial effects of this utility model are as follows: A power amplifier self-boost control circuit that can reduce delay includes an AC-DC module, a first filter module, a switching module, a buck module, a boost module, a second filter module, a DSP module, and a power amplifier module. The AC-DC module is connected to the AC power supply, the first filter module, the switching module, and the buck module. The boost module is connected to the buck module, the power amplifier module, and the battery. The DSP module is connected to the buck module and the power amplifier module. The switching module is connected to the power amplifier module. The power amplifier module is connected to the speaker. Through the above circuit, the first filter module acts as a large capacitor for filtering when powered by AC, and the second filter module acts as a small capacitor for filtering when powered by battery self-boost, thereby solving the boost delay problem without increasing the battery capacity. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0019] Figure 1 This is a circuit schematic of a power amplifier self-boost control circuit that can reduce delay.

[0020] Figure 2 This is the circuit schematic of the first filtering module;

[0021] Figure 3 This is the circuit schematic of the switching module;

[0022] Figure 4 This is the circuit schematic of the boost module;

[0023] Figure 5 This is the circuit schematic of the power amplifier module;

[0024] Figure 6 This is the circuit schematic of the second filter module;

[0025] Figure 7 This is the circuit schematic for a unidirectional conduction module. Detailed Implementation

[0026] This section will describe in detail the specific embodiments of the present utility model. The preferred embodiments of the present utility model are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present utility model, but they should not be construed as limiting the scope of protection of the present utility model.

[0027] In the description of this utility model, "multiple" means two or more; "greater than," "less than," and "exceeding" are understood to exclude the stated number; "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly specifying the number of indicated technical features or their sequential relationship.

[0028] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0029] In this utility model, unless otherwise explicitly defined, the terms "setting," "installing," and "connecting" should be interpreted broadly. For example, they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to a fixed connection, a detachable connection, or an integral molding; they can refer to a mechanical connection; they can refer to the internal connection of two components or the interaction between two components. Those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0030] Reference Figures 1 to 7 A power amplifier self-boost control circuit that can reduce latency includes an AC-DC module 10, a first filter module 20, a switching module 30, a buck module 40, a boost module 50, a second filter module 60, a DSP module 70, and a power amplifier module 80.

[0031] AC-DC module 10 is connected to AC power supply, first filter module 20, switch module 30 and step-down module 40 respectively;

[0032] The boost module 50 is connected to the buck module 40, the power amplifier module 80, and the battery, respectively.

[0033] The DSP module 70 is connected to the step-down module 40 and the power amplifier module 80, respectively.

[0034] Switch module 30 is connected to power amplifier module 80;

[0035] The power amplifier module 80 is connected to the speaker.

[0036] In this invention, the BOOST boost circuit (boost module 50) is composed of boost chip U3, inductor L9, MOSFET Q1, and diode D2, and the power amplifier module 80 mainly includes digital power amplifier chip U1. Specifically, the working principle of this invention is as follows:

[0037] 1)Reference Figure 1 and Figures 4-6When powered by a battery, the battery power is boosted by the boost module 50 and supplied to the power amplifier module 80. When the power amplifier module 80 receives digital audio from the DSP module 70, pin 9 of the digital power amplifier chip U1 outputs a PWM control signal according to the audio signal level. This signal, via resistors R26, R25, and R24, controls pin FB of the boost chip U3, causing the output voltage of the BOOST boost circuit to change with the audio level. In some embodiments, the second filter module 60 includes capacitors C25, C28, C29, and C30 connected in parallel. One end of the parallel connection is connected to both the boost module 50 and the power amplifier module 80, and the other end is connected to ground. The frequency of the OST boost circuit is usually relatively high (500KHz-2MHz). The filter capacitor C25 is 22uF, and capacitors C28, C29, and C30 are used for filtering at different high frequencies. The power supply pin of the digital power amplifier chip U1 also has a first-stage filter capacitor (capacitors C2, CB1, and CE1). The capacitance value of the filter capacitor in the second filter module 60 is relatively small, so the charging time is short, and the voltage can be boosted to the voltage required by the power amplifier module 80 within tens of microseconds. The power supply of the pre-amplifier DSP module 70 is provided by the battery through the step-down module 40, so that the ripple of the power amplifier module 80 will not interfere with the pre-amplifier DSP module 70 through the BOOST boost circuit, and the isolation effect is very good.

[0038] 2)Reference Figures 1-7When AC power is used, the AC power is converted from AC to DC and then stepped down by the AC-DC module 10, resulting in a relatively large capacitor filter. In some embodiments, the first filter module 20 includes capacitors CE3, C3, and CB5 connected in parallel. One end of the parallel connection is connected to the AC-DC module 10, the switch module 30, and the step-down module 40, respectively, and the other end is connected to the ground terminal. Preferably, the switch module 30 includes resistors R3-R6, a MOSFET Q2, and a transistor Q3. One end of resistor R3 is connected to one end of resistor R5, the drain of MOSFET Q2, the first filter module 20, and the switch module 30, respectively. The other end of resistor R3 is connected to the gate of MOSFET Q2 and one end of resistor R4, the other end of resistor R4 is connected to the collector of transistor Q3, and the base of transistor Q3 is connected to the other end of resistor R5. One end of the resistor is connected to the other end of the resistor R6. The other end of the resistor R6 is connected to the emitter of transistor Q3 and the ground terminal. The source of MOSFET Q2 is connected to the power amplifier module 80. The switching frequency of AC-DC module 10 is generally between 50KHz and 100KHz. The filter capacitors CE3, C3, and CB5 are 470uF-1000uF. The power supply of the pre-amplifier DSP module 70 is obtained by stepping down the voltage through the step-down module 40. The power supply of the power amplifier module 80 is connected to the power pin of the digital power amplifier chip U1 after MOSFET Q2 is turned on. Among them, resistors R3-R6, MOSFET Q2, and transistor Q3 form a switching circuit. When there is voltage on resistor R5, it is applied to the base of transistor Q3 through resistor R6. At this time, transistor Q3 is turned on, and the collector voltage of transistor Q3 becomes low. Resistors R3 and R4 divide the voltage, making the V of MOSFET Q2... GS With a voltage of 10V-15V, MOSFET Q2 is turned on, and the DC-VCC voltage is supplied to the PVCC pin of the digital power amplifier chip U1 through the drain and source of MOSFET Q2.

[0039] 3)Reference Figure 1 and Figure 7 In some embodiments, a power amplifier self-boost control circuit that can reduce delay further includes a unidirectional conduction module 90 connected between the first filter module 20, the switch module 30, the buck module 40, and the boost module 50; as a preferred embodiment of the unidirectional conduction module 90, the unidirectional conduction module 90 includes diodes D1 and D2, the anode of diode D1 is connected to the first filter module 20 and the switch module 30 respectively, the cathode of diode D1 is connected to the buck module 40 and the cathode of diode D2 respectively, and the anode of diode D2 is connected to the boost module 50.

[0040] 4) The advantages of this utility model are: the above circuit can use a first filter module as a large capacitor for filtering when AC power is supplied, and a second filter module as a small capacitor for filtering when the battery self-boosts the power supply, thereby solving the problem of boost delay without increasing the battery capacity.

[0041] Of course, this utility model is not limited to the above-described embodiments. Those skilled in the art can make equivalent modifications or substitutions without departing from the spirit of this utility model. All such equivalent modifications and substitutions are included within the scope defined by the claims of this application.

Claims

1. A power amplifier self-boost control circuit that can reduce delay, characterized in that: It includes an AC-DC module (10), a first filter module (20), a switching module (30), a buck module (40), a boost module (50), a second filter module (60), a DSP module (70), and a power amplifier module (80). The AC-DC module (10) is connected to the AC power supply, the first filter module (20), the switch module (30), and the step-down module (40), respectively. The boost module (50) is connected to the buck module (40), the power amplifier module (80), and the battery, respectively; The DSP module (70) is connected to the step-down module (40) and the power amplifier module (80) respectively; The switch module (30) is connected to the power amplifier module (80); The power amplifier module (80) is connected to the speaker.

2. The power amplifier self-boost control circuit with reduced delay according to claim 1, characterized in that: The first filter module (20) includes capacitors CE3, C3 and CB5 connected in parallel. One end of the parallel connection is connected to the AC-DC module (10), the switch module (30) and the step-down module (40) respectively, and the other end of the parallel connection is connected to the ground terminal.

3. The power amplifier self-boost control circuit with reduced delay according to claim 1, characterized in that: The switching module (30) includes resistors R3-R6, MOSFET Q2 and transistor Q3. One end of resistor R3 is connected to one end of resistor R5, the drain of MOSFET Q2, the first filter module (20) and the switching module (30). The other end of resistor R3 is connected to the gate of MOSFET Q2 and one end of resistor R4. The other end of resistor R4 is connected to the collector of transistor Q3. The base of transistor Q3 is connected to the other end of resistor R5 and the other end of resistor R6. The other end of resistor R6 and the emitter of transistor Q3 are connected to the ground terminal. The source of MOSFET Q2 is connected to the power amplifier module (80).

4. The power amplifier self-boost control circuit with reduced delay according to claim 1, characterized in that: The second filter module (60) includes capacitors C25, C28, C29 and C30 connected in parallel. One end of the parallel connection is connected to the boost module (50) and the power amplifier module (80) respectively, and the other end of the parallel connection is connected to the ground terminal.

5. The power amplifier self-boost control circuit with reduced delay according to claim 1, characterized in that: It also includes a unidirectional conduction module (90) connected between the first filter module (20), the switch module (30), the step-down module (40), and the boost module (50).

6. The power amplifier self-boost control circuit with reduced delay according to claim 5, characterized in that: The unidirectional conduction module (90) includes diode D1 and diode D2. The anode of diode D1 is connected to the first filter module (20) and the switch module (30) respectively. The cathode of diode D1 is connected to the buck module (40) and the cathode of diode D2 respectively. The anode of diode D2 is connected to the boost module (50).

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