TWI452515B - Circuit for providing power source to audio codec chip - Google Patents

Description

Audio coded chip power supply circuit

The present invention relates to a power supply circuit, and more particularly to a circuit for powering an audio coded chip.

The computer usually has an audio coded chip for providing audio output, and the computer main board is provided with a power supply circuit for supplying power to the audio coded chip. As shown in FIG. 1, a conventional audio coded chip power supply circuit includes a 12V motherboard power supply VS and a near 5V standby power supply VSB. The 12V motherboard power supply is converted to 5V by a voltage regulator and then connected to a first input end of a bipolar diode device. The 5V standby power supply VSB is connected to the second of the bipolar diode device. Input. The output of the bipolar diode device is connected to the power input VA of the audio coded chip. The above-mentioned audio coded chip power supply circuit is used. In some cases, the standby voltage VSB of the output of the power supply unit of the computer motherboard is greater than the output voltage of the 12V power supply board after the power supply is regulated. At this time, the bipolar diode device will select the standby voltage to be output to the audio coded chip. When the standby power supply directly supplies power to the audio coded chip, the ripple voltage generated is much larger than the ripple voltage generated when the regulator supplies the 12V power supply voltage to the audio coded chip, thereby outputting the audio coded chip. Noise is generated when audio.

In view of this, it is necessary to provide an audio encoder power supply circuit that can eliminate noise during audio output.

An audio coded chip power supply circuit includes a motherboard power supply, a first filter circuit, and a voltage regulator having an input end and an output end, wherein the input end of the voltage regulator is used by the first filter The circuit is connected to the power supply of the motherboard. The audio coded chip power supply circuit further includes a second filter circuit, and the output end of the voltage regulator is connected to the power input end of an audio coded chip by the second filter circuit for The audio coded chip is powered.

Compared with the prior art, the audio coded chip power supply circuit provided by the present invention removes the bipolar diode connected to the standby power supply and the output power of the voltage regulator on the motherboard, and adds a second filter circuit, thereby eliminating The ripple interference of the standby power supply to the audio coded chip power supply improves the output quality of the audio coded chip.

10‧‧‧ motherboard power supply

30‧‧‧First filter circuit

50‧‧‧Regulator

51‧‧‧ input

53, VS‧‧‧ output

G‧‧‧ Grounding terminal

F1‧‧‧first magnetic beads

C1‧‧‧first capacitor

C2‧‧‧second capacitor

M‧‧‧ node

60‧‧‧Second filter circuit

F2‧‧‧second magnetic beads

C3‧‧‧ third capacitor

C4‧‧‧fourth capacitor

80‧‧‧Audio coded chip

VA‧‧‧ power input

1 is a perspective exploded view of a preferred embodiment of an electronic device housing of the present invention.

Figure 2 is a perspective view of one of the brackets of Figure 1.

Figure 3 is an assembled view of Figure 1.

Referring to FIG. 2, the audio coded chip power supply circuit of the present invention comprises a motherboard power supply 10, a first filter circuit 30, a voltage regulator 50, a second filter circuit 60, and a power input terminal VA of an audio codec chip 80. . The voltage regulator 50 is connected to the motherboard power supply 10 by the first filter circuit 30, and is connected to the power input terminal 80 of the audio coded chip by the second filter circuit 60.

Please also refer to FIG. 3, the motherboard power supply 10 has an output terminal with an output voltage of 12V. VS. The first filter circuit 30 includes a first magnetic bead F1 connected to the output terminal Vs of the motherboard power supply 10, a first capacitor C1 and a second capacitor C2. The first capacitor C1 is connected in parallel with the second capacitor C2, and the other end is connected to the first magnetic bead F1. The capacitance of the first capacitor C1 is 10 μF, and the capacitance of the second capacitor C2 is 0.1 μF. The impedance of the first magnetic bead F1 is 80 ohms.

The regulator 50 has an input terminal 51, an output terminal 53 and a ground terminal G. The input terminal 51 of the voltage regulator 50 is connected to the common node M of the first magnetic bead F1, the first capacitor C1 and the second capacitor C2. In the present embodiment, the type of the regulator 50 is L78L05.

The second filter circuit 60 includes a second magnetic bead F2 connected to the output end 53 of the voltage regulator 50, a third capacitor C3 and a fourth capacitor C4. The third capacitor C3 is connected in parallel with the fourth capacitor C4, and the other end is connected to the second magnetoresistive resistor F2 and the power input terminal VA of the audio encoding chip. The resistance of the third capacitor C3 and the fourth capacitor C4 is 0.1 μF. The impedance of the second magnetic bead F2 is 100 ohms.

When the motherboard power supply 10 is powered on, the output VS of the motherboard power supply 10 outputs a DC voltage of 12V. The 12V DC voltage is filtered and rectified by the first filter circuit 30, and then transmitted to the regulator 50 for voltage conversion, and the 12V power supply voltage is converted into a voltage of 5V. The 5V voltage is filtered by the second filter circuit 60 and transmitted to the power input terminal VA of the audio codec chip, thereby eliminating high frequency signals in the signal transmission process from interfering with the power supply of the audio codec chip, thereby generating ripple interference noise.

The audio coded chip power supply circuit provided by the invention removes the bipolar diode connected to the standby power supply and the output power of the voltage regulator on the motherboard, and adds a second filter circuit, thereby eliminating the audio coding of the standby power supply. The ripple interference of the chip power supply improves the output quality of the audio coded chip.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

30‧‧‧First filter circuit

50‧‧‧Regulator

51‧‧‧ input

53, VS‧‧‧ output

G‧‧‧ Grounding terminal

F1‧‧‧first magnetic beads

C1‧‧‧first capacitor

C2‧‧‧second capacitor

M‧‧‧ node

60‧‧‧Second filter circuit

F2‧‧‧second magnetic beads

C3‧‧‧ third capacitor

C4‧‧‧fourth capacitor

VA‧‧‧ power input

Claims (7)

An audio coded chip power supply circuit includes a motherboard power supply, a first filter circuit, and a voltage regulator having an input end and an output end, wherein the input end of the voltage regulator is used by the first filter The circuit is connected to the power supply of the motherboard. The audio coded chip power supply circuit further includes a second filter circuit, and the output end of the voltage regulator is connected to the power input end of an audio coded chip by the second filter circuit for The second filter circuit includes a second magnetic bead connected to the voltage regulator, a third capacitor and a fourth capacitor. The third capacitor is connected in parallel with the fourth capacitor, and the other end is grounded. Connected to the second magnetoresistive and the power input end of the audio coded chip, respectively. The audio coded chip power supply circuit of claim 1, wherein: the power supply of the motherboard is 12V, and the voltage converter converts the power of the 12V motherboard into a power supply of 5V to the power input end of the audio coded chip. The audio coded chip power supply circuit of claim 1, wherein the first filter circuit comprises a first magnetic bead connected to the power supply of the motherboard, a first capacitor and a second capacitor, the first capacitor and the first capacitor After the two capacitors are connected in parallel, one end is grounded, and the other end is connected to the first magnetic bead. The voltage regulator is connected to a common node of the first magnetic bead, the first capacitor and the second capacitor. The audio coded chip power supply circuit of claim 3, wherein the magnetic bead has an impedance value of 80 ohms. The audio coded chip power supply circuit of claim 3, wherein the first capacitor has a capacitance of 10 μF and the second capacitor has a capacitance of 0.1 μF. The audio coded chip power supply circuit of claim 1, wherein: the second magnetic bead has an impedance value of 100 ohms. The audio coded chip power supply circuit of claim 1, wherein: the third capacitor and the fourth capacitor The capacitance is 0.1 μF.