CN204887411U - Intelligence audio frequency drive circuit - Google Patents

Abstract

The utility model relates to an intelligent audio drive circuit, comprising a fuse F1, an adjustable resistor VR1, a rectifier bridge BR1, an inductance L1, an inductance L2, a resistor R1 to a resistor R15, a capacitor C1 to a capacitor C9, a diode D1, a diode D2, a diode D3, and a transformer T1, audio device, PWM converter chip U1, photocoupler U2 and controllable voltage regulator U3; one end of the fuse F1 is connected to the live wire end of the mains, and the other end of the fuse F1 and one end of the adjustable resistor VR1 are connected to the rectifier bridge The positive input terminal of BR1 is connected, and the other end of the adjustable resistor VR1 and the negative input terminal of the rectifier bridge BR1 are connected to the neutral terminal of the mains; the utility model drives the audio power supply through the PWM converter chip, which can prevent the circuit peak Generated, avoiding the interference of the audio driver on the audio device, and having a protective effect on the circuit.

Description

Intelligent Audio Driver Circuit

technical field

The utility model relates to an intelligent audio drive circuit.

Background technique

At present, there are many audio devices on the market. In order to realize the functions of audio devices, audio drive circuits are required. The existing audio drive power supply is insufficient, especially in the treble part of the audio. On the other hand, the current drive dynamic response time is long, because the audio device needs a dynamic current, sometimes high, sometimes low, if the dynamic If the response time is not enough, a current spike will be generated. Any of the above two points will cause sound to the audio, which will affect the sound quality, generate noise, and affect people's perception of sound hearing.

Utility model content

In view of the above technical problems, the purpose of this utility model is to provide an intelligent audio drive circuit with low cost and excellent performance, which can effectively avoid the generation of current peaks.

In order to achieve the above object, the utility model adopts the following technical solutions:

Intelligent audio drive circuit, including fuse F1, adjustable resistor VR1, rectifier bridge BR1, inductor L1, inductor L2, resistor R1 to resistor R15, capacitor C1 to capacitor C9, diode D1, diode D2, diode D3, transformer T1, audio components , PWM converter chip U1, photocoupler U2 and controllable voltage regulator U3;

One end of the fuse F1 is connected to the live wire end of the mains, the other end of the fuse F1 and one end of the adjustable resistor VR1 are connected to the positive input of the rectifier bridge BR1, and the other end of the adjustable resistor VR1 is connected to the negative input of the rectifier bridge BR1 Both terminals are connected to the neutral terminal of the mains; the positive output terminal of the rectifier bridge BR1 and one end of the capacitor C1 are connected to one end of the inductor L1, and the other end of the inductor L1 and one end of the capacitor C2 are connected to one end of the resistor R1 , the negative output end of the rectifier bridge BR1, the other end of the capacitor C1 and the other end of the capacitor C2 are all grounded; one end of the resistor R1, one end of the capacitor C3, one end of the resistor R2 and one end of the resistor R3 are all connected to the first primary of the transformer T1 One end of the coil is connected, the other end of the capacitor C3, the other end of the resistor R2 and the other end of the resistor R3 are all connected to one end of the resistor R4, the other end of the resistor R4 is connected to the negative pole of the diode D1, the positive pole of the diode D1 is connected to the transformer T1 The other end of the first primary coil is connected to the first open-drain end of the PWM converter chip U1; the first open-drain end of the PWM converter chip U1 is connected to the second open-drain end of the PWM converter chip U1; the resistance R1 The other end is connected to one end of the resistor R5, the other end of the resistor R5, one end of the resistor R6 and one end of the capacitor C4 are all connected to the power input end of the PWM converter chip U1, the other end of the resistor R6 is connected to the cathode of the diode D2, and the other end of the diode D2 The anode is connected to one end of the second primary coil of the transformer T1, and the other end of the second primary coil of the transformer T1 and the other end of the capacitor C4 are grounded; one end of the secondary coil of the transformer T1 and one end of the resistor R7 are connected to the diode D3 The other end of the resistor R7 is connected to one end of the capacitor C5, the other end of the capacitor C5, one end of the capacitor C6 and the negative electrode of the diode D3 are connected to one end of the inductor L2, the other end of the inductor L2, one end of the capacitor C7 and the resistor One end of R8 is all connected with the positive pole of the audio device, the other end of the secondary coil of the transformer T1, the other end of the capacitor C6, the other end of the capacitor C7 and the other end of the resistor R8 are all connected with the negative pole of the audio device; resistor R9 One end of the resistor R10 and one end of the resistor R10 are connected to the other end of the capacitor C5, the other end of the resistor R9 and one end of the resistor R11 are connected to one end of the resistor R12, and one end of the resistor R12 is also connected to the reference end of the controllable voltage regulator U3. The other end of the resistor R12 and the positive end of the controllable voltage regulator U3 are both connected to the other end of the resistor R8, the other end of the resistor R11 is connected to one end of the capacitor C8, and the other end of the capacitor C8 is connected to the controllable voltage regulator U3. Both the negative terminal and one end of the resistor R13 are connected to the negative input terminal of the optocoupler U2, the other end of the resistor R10 and the other end of the resistor R13 are connected to the positive input terminal of the optocoupler U2, and one end of the capacitor C9 and the positive output end of the photocoupler U2 are connected to the feedback end of the PWM converter chip U1, and one end of the resistor R14 and one end of the resistor R15 are connected to the current detection end of the PWM converter chip U1 connected, the other end of the capacitor C9, the other end of the resistor R14, the other end of the resistor R15, the ground end of the PWM converter chip U1 and the negative output end of the optocoupler U2 are all grounded.

Preferably, the model of the PWM converter chip U1 is WS229XD7P.

Compared with the prior art, the beneficial effects of the utility model are:

The utility model drives the audio power supply to work through the PWM converter chip, can eliminate the generation of circuit spikes, avoids the interference of the audio drive to the audio device, and has a protective effect on the circuit.

Description of drawings

Fig. 1 is a circuit structure diagram of the utility model.

Detailed ways

Below, in conjunction with accompanying drawing and specific embodiment, the utility model is described further:

Referring to Fig. 1, the utility model provides an intelligent audio drive circuit, including fuse F1, adjustable resistor VR1, rectifier bridge BR1, inductor L1, inductor L2, resistor R1 to resistor R15, capacitor C1 to capacitor C9, diode D1, diode D2, diode D3, transformer T1, audio device, PWM converter chip U1, photocoupler U2 and controllable voltage regulator U3.

The specific connection relationship is: one end of the fuse F1 is connected to the live wire end of the mains, the other end of the fuse F1 and one end of the adjustable resistor VR1 are connected to the positive input terminal 1 of the rectifier bridge BR1, and the other end of the adjustable resistor VR1 is connected to the rectifier bridge. The negative input terminal 2 of BR1 is connected to the neutral terminal of the mains; the positive output terminal 3 of the rectifier bridge BR1 and one end of the capacitor C1 are connected to one end of the inductor L1, and the other end of the inductor L1 and one end of the capacitor C2 are connected to the resistor One end of R1 is connected, the negative output terminal 4 of rectifier bridge BR1, the other end of capacitor C1 and the other end of capacitor C2 are all grounded; one end of resistor R1, one end of capacitor C3, one end of resistor R2 and one end of resistor R3 are all connected to the transformer One end of the first primary coil of T1 is connected, the other end of capacitor C3, the other end of resistor R2 and the other end of resistor R3 are all connected to one end of resistor R4, the other end of resistor R4 is connected to the negative pole of diode D1, and the other end of diode D1 The positive pole and the other end of the first primary coil of the transformer T1 are connected to the first open drain end a of the PWM converter chip U1; the first open drain end a of the PWM converter chip U1 is connected to the second open drain end a of the PWM converter chip U1 The drain terminal b is connected; the other end of the resistor R1 is connected to one end of the resistor R5, the other end of the resistor R5, one end of the resistor R6, and one end of the capacitor C4 are connected to the power input terminal c of the PWM converter chip U1, and the other end of the resistor R6 Connect the cathode of the diode D2, the anode of the diode D2 is connected to one end of the second primary coil of the transformer T1, the other end of the second primary coil of the transformer T1 and the other end of the capacitor C4 are both grounded; one end of the secondary coil of the transformer T1 One end of resistor R7 is connected to the positive pole of diode D3, the other end of resistor R7 is connected to one end of capacitor C5, the other end of capacitor C5, one end of capacitor C6 and the negative pole of diode D3 are connected to one end of inductor L2, and the The other end, one end of the capacitor C7 and one end of the resistor R8 are all connected to the positive pole of the audio device, the other end of the secondary coil of the transformer T1, the other end of the capacitor C6, the other end of the capacitor C7 and the other end of the resistor R8 are all Connect to the negative pole of the audio device; one end of resistor R9 and one end of resistor R10 are connected to the other end of capacitor C5, the other end of resistor R9 and one end of resistor R11 are connected to one end of resistor R12, and one end of resistor R12 can also be connected The reference end of the controllable voltage source U3, the other end of the resistor R12 and the positive end of the controllable voltage source U3 are connected to the other end of the resistor R8, the other end of the resistor R11 is connected to one end of the capacitor C8, and the other end of the capacitor C8 One end, the negative end of the controllable voltage regulator U3 and one end of the resistor R13 are all connected to the negative input end of the optocoupler U2, and the other end of the resistor R10 and the other end of the resistor R13 are connected to the positive input of the optocoupler U2 One end of the capacitor C9 and the positive output end of the photocoupler U2 are connected to the feedback end d of the PWM converter chip U1, and one end of the resistor R14 and one end of the resistor R15 are connected to the PWM conversion The current detection terminal e of the converter chip U1 is connected, the other end of the capacitor C9, the other end of the resistor R14, the other end of the resistor R15, the ground terminal f of the PWM converter chip U1, and the negative output terminal of the photocoupler U2 are all grounded .

When the current detection terminal is open, the PWM converter chip U1 will not send any pulses and enter the automatic restart mode. The input level value of the feedback terminal and the current detection terminal jointly determine the duty cycle of the PWM control signal. If the input voltage of the feedback terminal is greater than the preset threshold voltage, the internal protection circuit will automatically turn off the PWM output, which will affect the audio device. to the protective effect. The PWM converter chip U1 has a built-in power transistor, and the open drain terminal is the drain of the built-in power transistor, which is connected to the primary side of the transformer t1. When working, the PWM converter chip U1 drives its switching frequency to change with the current required by the audio device. When the current is large, its switching frequency is high, and the current is more hot, which completely eliminates the generation of current spikes. It eliminates the interference of the driver on the audio device, and the dynamic response time of the audio driver through the PWM converter chip U1 is only 2um, and there will be no sound lag.

The model of the above-mentioned PWM converter chip U1 is preferably WS229XD7P.

WS229XD7P is a highly integrated, high-performance current mode PWM converter chip, suitable for small and medium power (60W) switching power supply equipment and switching power converters such as power adapters. It has a wide operating voltage range (7.7V-34V), which improves the compatibility of the system.

For those skilled in the art, various other corresponding changes and deformations can be made according to the technical solutions and ideas described above, and all these changes and deformations should fall within the protection scope of the claims of the present utility model.

Claims (2)

1. intelligent audio drive circuit, it is characterized in that, comprise fuse F1, adjustable resistance VR1, rectifier bridge BR1, inductance L 1, inductance L 2, resistance R1 to resistance R15, electric capacity C1 to electric capacity C9, diode D1, diode D2, diode D3, transformer T1, audio parts, PWM converter chip U1, photoelectrical coupler U2 and controlled source of stable pressure U3;

One end of described fuse F1 connects the live wire end of civil power, the other end of fuse F1 is all connected with the electrode input end of rectifier bridge BR1 with one end of adjustable resistance VR1, and the other end of adjustable resistance VR1 is all connected with the zero line side of civil power with the negative input of rectifier bridge BR1, the cathode output end of described rectifier bridge BR1 is all connected with one end of inductance L 1 with one end of electric capacity C1, the other end of inductance L 1 is all connected with one end of resistance R1 with one end of electric capacity C2, the equal ground connection of the other end of the cathode output end of rectifier bridge BR1, the other end of electric capacity C1 and electric capacity C2, one end of one end of resistance R1, one end of electric capacity C3, resistance R2 is all connected with one end of first primary coil of transformer T1 with one end of resistance R3, the other end of electric capacity C3, the other end of resistance R2 are all connected with one end of resistance R4 with the other end of resistance R3, the other end of resistance R4 connects the negative pole connection of diode D1, and the positive pole of diode D1 is all opened drain terminal with first of PWM converter chip U1 with the other end of first primary coil of transformer T1 and is connected, first of PWM converter chip U1 opens drain terminal and opens drain terminal with second of PWM converter chip U1 and be connected, one end of the other end contact resistance R5 of resistance R1, the other end of resistance R5 is all connected with the power input of PWM converter chip U1 with one end of electric capacity C4 with one end of resistance R6, the other end of resistance R6 connects the negative pole of diode D2, one end of second primary coil of the positive pole connection transformer T1 of diode D2, the other end of second primary coil of transformer T1 and the equal ground connection of the other end of electric capacity C4, one end of the secondary coil of described transformer T1 is all connected with the positive pole of diode D3 with one end of resistance R7, the other end of resistance R7 connects one end of electric capacity C5, the other end of electric capacity C5, one end of electric capacity C6 are all connected with one end of inductance L 2 with the negative pole of diode D3, the other end of inductance L 2, one end of electric capacity C7 are all connected with the positive pole of audio parts with one end of resistance R8, and the other end of the secondary coil of described transformer T1, the other end of electric capacity C6, the other end of electric capacity C7 are all connected with the negative pole of audio parts with the other end of resistance R8, one end of resistance R9 is all connected with the other end of electric capacity C5 with one end of resistance R10, the other end of resistance R9, one end of resistance R11 is all connected with one end of resistance R12, one end of resistance R12 also connects the reference edge of controlled source of stable pressure U3, the other end of described resistance R12 is all connected with the other end of resistance R8 with the positive terminal of controlled source of stable pressure U3, the other end of resistance R11 connects one end of electric capacity C8, the other end of electric capacity C8, the negative pole end of controlled source of stable pressure U3 is all connected with the negative input of photoelectrical coupler U2 with one end of resistance R13, the other end of described resistance R10 is all connected with the electrode input end of photoelectrical coupler U2 with the other end of resistance R13, one end of described electric capacity C9 is all connected with the feedback end of PWM converter chip U1 with the cathode output end of photoelectrical coupler U2, one end of described resistance R14 is all connected with the current detecting end of PWM converter chip U1 with one end of resistance R15, the other end of described electric capacity C9, the other end of resistance R14, the other end of resistance R15, the ground end of PWM converter chip U1 and the equal ground connection of cathode output end of photoelectrical coupler U2.

2. intelligent audio drive circuit as claimed in claim 1, it is characterized in that, the model of described PWM converter chip U1 is WS229XD7P.