KR20210135847A - Audio electronic device including buck converter and method of operation thereof - Google Patents

Abstract

Disclosed is an electronic device including a power circuit including a buck converter; a communication circuit; at least one processor operatively connected with the power circuit and the communication circuit; and a memory operatively connected with the at least one processor. The memory can store at least one instruction which, when executed, causes the at least one processor to: receive information related to the conversion of an audio signal, including at least one among an audio codec, an audio bandwidth, and a sampling rate, from an external electronic device connected by the communication circuit; and change a switching frequency of the buck converter based on at least a part of the information related to the conversion of the audio signal. Besides, various embodiments identified through the specification can be possible. Therefore, the present invention is capable of minimizing a noise in an audible frequency band.

Description

An audio electronic device including a buck converter and an operating method thereof

Various embodiments disclosed in this document relate to an audio electronic device including a buck converter and an operating method thereof.

Recently, the use of audio accessory devices such as USB (Universal Serial Bus) Type-C earphones and Bluetooth earphones is increasing. In order to increase the usage time of these audio accessory devices, a high-efficiency DC-DC converter is used. is configured in the power supply circuit. According to an embodiment, in the audio accessory device, a buck converter using an inductor and a capacitor to easily obtain a voltage of a target level while minimizing power consumption may be used as a DC-DC converter. have.

A buck converter is a power circuit that converts an input voltage to a lower DC voltage.

According to various embodiments disclosed in this document, it is possible to provide an audio electronic device that minimizes noise in an audible frequency band and has high power efficiency, and an operating method thereof.

An audio electronic device according to an embodiment disclosed in this document includes a power circuit including a buck converter, a communication circuit, at least one processor operatively connected to the power circuit and the communication circuit, and the at least a memory operatively coupled to one processor, wherein the memory, when executed, causes the at least one processor to provide audio codec, audio bandwidth and One or more instructions for receiving information related to conversion of an audio signal, including at least one of a sampling rate, and changing a switching frequency of the buck converter based on at least a portion of the information related to conversion of the audio signal You can store instructions.

In addition, the method of operating an audio electronic device including a buck converter according to an embodiment disclosed in this document includes an audio codec from an external electronic device connected to the audio electronic device by a communication circuit; An operation of receiving information related to conversion of an audio signal, including at least one of an audio bandwidth and a sampling rate, and at least a portion of the information related to conversion of the audio signal of the buck converter It may include an operation of changing the switching frequency.

According to various embodiments disclosed in this document, it is possible to provide an audio electronic device including a buck converter capable of minimizing noise in an audible frequency band while maximizing power efficiency under a light load condition, and an operating method thereof.

In addition, various effects directly or indirectly identified through this document may be provided.

1 is a block diagram of an audio electronic device according to an exemplary embodiment.
2 is a block diagram of an audio electronic device according to an exemplary embodiment.
3 is a flowchart illustrating a method of operating an audio electronic device according to an exemplary embodiment.
4 is a circuit diagram of a hysteresis buck converter according to an embodiment.
5 is a diagram illustrating an audio noise reduction method according to a change in a hysteresis threshold of an audio electronic device according to an exemplary embodiment.
6 is a diagram illustrating a change in audio noise according to a change in a switching frequency of a hysteresis buck converter according to an exemplary embodiment.
7 is a diagram illustrating an example of an audio bandwidth according to an audio codec or a sampling rate.
8 is a block diagram of an audio electronic device according to another exemplary embodiment.
9 is a flowchart illustrating a method of operating an audio electronic device according to an exemplary embodiment.
In connection with the description of the drawings, the same or similar reference numerals may be used for the same or similar components.

Hereinafter, various embodiments of the present invention will be described with reference to the accompanying drawings. However, this is not intended to limit the present invention to specific embodiments, and it should be understood that various modifications, equivalents, and/or alternatives of the embodiments of the present invention are included.

Hereinafter, a configuration of an audio electronic device according to an exemplary embodiment will be described with reference to FIG. 1 .

1 is a block diagram 100 of an audio electronic device according to an embodiment. According to an embodiment, the audio electronic device 101 may be a Universal Serial Bus (USB) Type-C earphone, but is not limited thereto, and may include various USB audio accessory devices such as a USB headset and a USB speaker.

Referring to FIG. 1 , an audio electronic device 101 according to an embodiment may include a USB physical layer (PHY) 120 and a USB controller 125 . According to an embodiment, the audio electronic device 101 may perform USB communication with the external electronic device 102 based on the USB PHY 120 and the USB controller 125 .

The USB PHY 120 may receive an external signal and change it into a signal usable inside the system. The USB PHY 120 may decrypt encrypted data or demodulate modulated data. According to an embodiment, the USB PHY 120 may be implemented as a chip, and may be integrated into a USB controller (eg, the USB controller 125 ).

The USB controller 125 may control communication between the audio electronic device 101 and the external electronic device 102 connected thereto. According to an embodiment, when the audio electronic device 101 is connected to the external electronic device 102 through a USB connector (not shown), the USB controller 125 receives data or a command from the external electronic device 102, or It is possible to control to transmit data or a command to the external electronic device 102 .

According to an embodiment, the external electronic device 102 may correspond to a host device with respect to the audio electronic device 101 . According to an embodiment, the external electronic device 102 may include a portable communication device (eg, a smartphone), a computer device (eg, a personal digital assistant (PDA), a tablet PC), or a laptop PC (eg, a desktop PC, a workstation). , or a server), a portable multimedia device (eg, an e-book reader or an MP3 player), or a wearable device.

Referring to FIG. 1 , the external electronic device 102 according to an embodiment may include a USB PHY 180 and a USB controller 185 . According to an embodiment, the USB PHY 180 and the USB controller 185 of the external electronic device 102 may correspond to the USB PHY 120 and the USB controller 125 of the audio electronic device 101 , respectively.

According to an embodiment, the USB PHY 120 and the USB controller 125 may be connected to other components of the audio electronic device 101 directly or through the system bus matrix 190 . The system bus matrix 190 includes components (eg, USB PHY 120 , USB controller 125 , RAM 142 , audio DMA controller 152 , audio codec 154 , flash memory 144 , peripherals). It may include a circuit that connects the device 160 and the microcontroller 130 to each other and transmits a signal (eg, a control message or data) between the components.

According to an embodiment, the USB controller 125 may control data received from the external electronic device 102 to be transmitted to the USB RAM 143 . In another embodiment, the USB controller 125 may control to transmit audio data received from the external electronic device 102 to the flash RAM 142 through the system bus matrix 190 .

According to an embodiment, the audio electronic device 101 may include a microcontroller 130 . According to an embodiment, the microcontroller 130 drives an operating system or an application program to control at least one other component (eg, a hardware or software component) of the audio electronic device 101 connected to the microcontroller 130 . It can control and perform various data processing and calculations. The microcontroller 130 loads and processes commands or data received from at least one of the other components (eg, the USB controller 125) into a volatile memory (eg, the RAM 142, or the USB RAM 143). and the result data may be stored in a non-volatile memory (eg, the flash memory 144).

According to an embodiment, the audio electronic device 101 may include an audio direct memory access (DMA) controller 152 . According to an embodiment, the audio DMA controller 152 transmits audio data to a memory (eg, RAM 142) and a memory (eg, flash memory) without going through a central processing unit (CPU) (eg, microcontroller 130). (143)), or a memory (eg, RAM 142) and an input/output device (not shown) can be controlled to transmit directly.

According to an embodiment, the audio electronic device 101 may include a random access memory (RAM) 142 . According to an embodiment, when the audio electronic device 101 is a USB device, the USB RAM 143 may be included. According to an embodiment, the audio electronic device 101 may include a flash memory 144 . The RAM 142 , the USB RAM 143 , and the flash memory 144 are at least one other component of the audio electronic device 101 (eg, the USB controller 125 , the microcontroller 130 , or the audio DMA controller). command or data received from (152)).

According to an embodiment, the audio electronic device 101 may include an audio codec 154 . The audio codec 154 may interactively convert a sound and an electrical signal. According to an embodiment, the audio codec 154 encodes a sound acquired through an input device (not shown) (eg, a microphone) of the audio electronic device 101 into a digital signal, and is connected to the audio electronic device 101 . Audio data received from the external electronic device 102 may be decoded. According to an embodiment, the audio electronic device 101 may transmit encoded audio data to the external electronic device 102 connected to the audio electronic device 101 . According to an embodiment, the audio electronic device 101 outputs audio data decoded by the audio codec 154 as sound through an output device (not shown) (eg, a speaker) included in the audio electronic device 101 . can do.

According to an embodiment, the audio electronic device 101 may include a peripheral device 160 . According to an embodiment, the peripheral device 160 may include, but is not limited to, the above-described input device and output device. It may further include a memory device.

According to an embodiment, the audio electronic device 101 may include a power circuit 110 . According to an embodiment, the power circuit 110 includes a hysteresis buck converter 112 and a linear regulator (Low Dropout, LDO) 114 to efficiently manage power of the audio electronic device 101 . may include. According to an embodiment, the linear regulator 114 may operate even with a low input/output potential difference (eg, 1 V or less), thereby reducing energy loss and suppressing heat generation.

According to an embodiment, the hysteresis buck converter 112 may convert a high DC voltage into a lower DC voltage. According to an embodiment, the hysteresis buck converter 112 is a pull-up switch and a pull-down switch on/off based on a comparison result by a hysteresis comparator. can control According to an embodiment, the hysteresis comparator may output a comparison result using the _{reference voltage V ref of a specific band.} Accordingly, the audio electronic device 101 according to an embodiment may have a high-speed transient response characteristic and ensure stability by configuring the hysteresis buck converter 112 in the power circuit 110 .

According to an embodiment, the switching frequency of the hysteresis buck converter 112 may vary according to a load condition. According to an embodiment, the hysteresis buck converter 112 may operate with pulse frequency modulation or may operate with pulse width modulation. According to an embodiment, the hysteresis buck converter 112 operating by pulse frequency modulation may operate with high efficiency by adjusting the switching frequency based on the output voltage under a low load condition. In this case, the lower the switching frequency, the higher the efficiency may be.

However, according to an embodiment, a low switching frequency under a light load condition generates a large current ripple, and noise may be generated by the current ripple. According to an embodiment, when the switching frequency is included in the audible frequency band, the user of the audio electronic device 101 may recognize the noise.

The audio electronic device 101 according to various embodiments disclosed herein may remove noise in the audible frequency band due to the switching frequency while maintaining high power efficiency by adjusting the switching frequency of the hysteresis buck converter 112 .

In the present disclosure, the hysteresis threshold of the hysteresis buck converter 112 may include a first hysteresis threshold and a second hysteresis threshold. In this case, the first hysteresis threshold value may be smaller than the second hysteresis threshold value. According to an embodiment, the audio electronic device 101 may remove noise in the audible frequency band due to switching in the switching frequency by adjusting the first hysteresis threshold based on the audio bandwidth, and the audio electronic device High power efficiency can be maintained by adjusting the second hysteresis threshold based on the load condition of (101).

The audio electronic device 101 according to various embodiments disclosed in this document exemplifies a case in which the buck converter is a hysteresis buck converter, but is not limited thereto, and includes various types of buck converters that do not include a hysteresis comparator. can do.

Hereinafter, a configuration and operation of an audio electronic device according to an exemplary embodiment will be described with reference to FIGS. 2 and 3 .

2 is a block diagram 200 of an audio electronic device according to an embodiment. According to an embodiment, the audio electronic device 201 of FIG. 2 may be the audio electronic device 101 of FIG. 1 . According to an embodiment, the audio electronic device 201 may be a USB audio accessory device such as a USB Type-C earphone, a USB headset, or a USB speaker.

Referring to FIG. 2 , the audio electronic device 201 according to an embodiment may include a power circuit 210 , a communication circuit 220 , a processor 230 , a memory 240 , and an audio module 250 . have. According to an embodiment, the power circuit 210 may include a hysteresis buck converter 212 .

According to an embodiment, the power circuit 210 may correspond to the power circuit 110 of FIG. 1 . The power circuit 210 may supply power to the audio electronic device 201 . According to an embodiment, the power circuit 210 may provide a high-efficiency energy efficiency by including the hysteresis buck converter 212 . According to an embodiment, the hysteresis buck converter 212 may correspond to the hysteresis buck converter 112 of FIG. 1 .

According to an embodiment, the communication circuit 220 may correspond to the USB PHY 120 and the USB controller 125 of FIG. 1 . According to an embodiment, the communication circuit 220 may connect the audio electronic device 201 and an external electronic device (eg, the external electronic device 102 of FIG. 1 ). In the embodiment described with reference to FIG. 1 , a case in which the audio electronic device and the external electronic device are connected through USB communication is exemplified, but the present invention is not limited thereto. (eg, Bluetooth communication connection).

According to an embodiment, the processor 230 may correspond to the microcontroller 130 of FIG. 1 . According to an embodiment, the processor 230 may control at least one other component (eg, a hardware or software component) of the audio electronic device 101 connected to the processor 230 by driving an operating system or an application program. and can perform various data processing and calculations. The processor 230 loads and processes a command or data received from at least one of the other components (eg, the communication circuit 220) into a volatile memory (eg, the RAM 142 of FIG. 1) and processes the result data. It may be stored in a non-volatile memory (eg, the flash memory 144 of FIG. 1 ).

The memory 240 may include a volatile memory or a non-volatile memory. According to an embodiment, the volatile memory may include the RAM 142 or the USB RAM 143 of FIG. 1 . According to an embodiment, the non-volatile memory may include the flash memory 144 of FIG. 1 .

According to an embodiment, the memory 240 stores instructions or data received from at least one other component of the audio electronic device 201 (eg, the processor 230 or the communication circuit 220). can

According to an embodiment, the audio module 250 may include the audio codec 154 of FIG. 1 . According to an embodiment, the audio module 250 may interactively convert a sound and an electrical signal. According to an embodiment, the audio module 250 may obtain a sound through an input device (eg, a microphone) or may output a sound through an output device (eg, a speaker) included in the audio electronic device 201 . have.

3 is a flowchart 300 illustrating a method of operating an audio electronic device according to an exemplary embodiment. An operation of the audio electronic device (eg, the audio electronic device 201 of FIG. 2 ) described below with reference to FIG. 3 may be performed by the processor 230 of FIG. 2 . According to an embodiment, the audio electronic device may be a USB audio accessory device.

Referring to FIG. 3 , in operation 301 , the audio electronic device according to an embodiment may be connected to an external electronic device (eg, the external electronic device 102 of FIG. 1 ) by wire through a communication circuit. According to one embodiment, the communication circuit of the audio electronic device may include a USB PHY (eg, USB PHY 120 in FIG. 1 ) and a USB controller (eg, USB controller 125 in FIG. 1 ) to support USB communication. can In this case, the communication circuit of the external electronic device may also include a USB PHY (eg, USB PHY 180 of FIG. 1 ) and a USB controller (eg, USB controller 185 of FIG. 1 ) to support USB communication.

In operation 302, the audio electronic device may receive information related to conversion of an audio signal from an external electronic device. According to an embodiment, the information related to the conversion of the audio signal may include at least one of an audio codec, an audio bandwidth, and a sampling rate.

According to an embodiment, before performing operation 302, the audio electronic device may receive an information request from the external electronic device as the audio electronic device is connected to the external electronic device. According to an embodiment, the audio electronic device may transmit information including at least one sampling rate supported by the audio electronic device to the external electronic device in response to an information request from the external electronic device. According to an embodiment, the information may be a device descriptor.

According to an embodiment, in operation 302, the audio electronic device may receive a sampling rate selected by the external electronic device from among at least one sampling rate supported by the audio electronic device. According to an embodiment, the audio electronic device may determine the sampling rate of the audio codec (eg, the audio codec 154 of FIG. 1 ) based on the sampling rate received from the external electronic device.

In the above-described embodiment, transmission of the sampling rate supported by the audio electronic device to the external electronic device and receiving the selected sampling rate from the external electronic device are exemplified. As another example, the bit depth supported by the audio electronic device is exemplified. ) may be transmitted to the external electronic device, and the selected bit depth may be further received from the external electronic device. In this case, the audio electronic device may determine the sampling rate of the audio codec further based on the bit depth received from the external electronic device.

According to an embodiment, when the audio electronic device is connected to the external electronic device by USB, USB enumeration may be performed between the audio electronic device and the external electronic device. According to an embodiment, the external electronic device connected to the audio electronic device may be referred to as a host device.

According to an embodiment, when the audio electronic device is connected to the host device, the host device may read the device descriptor from the audio electronic device through enumeration. According to an embodiment, the device descriptor may include a sampling rate and/or a bit depth supported by the audio electronic device.

According to an embodiment, the host device may activate an audio streaming interface by selecting an operational interface. By activating the audio streaming interface, the host device can start playback and recording of audio.

According to an embodiment, the host device may select at least one sampling rate or bit depth supported by the audio electronic device. The host device may select an operational interface based on the selected sampling rate or bit depth. Before transmitting an AudioStreaming Packet to the audio electronic device, the host device may transmit setting values for setting the interface of the audio electronic device according to the selected operator interface to the audio electronic device.

According to an embodiment, the audio electronic device may determine the sampling rate of the audio codec and the switching frequency of the hysteresis buck converter based on setting values received from the host device. Hereinafter, an operation (operation 303 ) in which the audio electronic device changes the switching frequency of the hysteresis buck converter will be described in detail.

In operation 303, the audio electronic device may change the switching frequency of the buck converter (eg, the hysteresis buck converter 212 of FIG. 2 ) based on at least a part of information related to conversion of an audio signal received from the external electronic device. As described above, the information related to the conversion of the audio signal may include at least one of an audio codec, an audio bandwidth, and a sampling rate. According to an embodiment, the audio electronic device may change the switching frequency of the buck converter based on an audio bandwidth determined according to a sampling rate.

According to an embodiment, when the sampling rate is less than twice the audio bandwidth, audio data may not be completely restored. In other words, the sampling rate may have to be at least twice the audio bandwidth. Accordingly, according to an embodiment, the audio bandwidth may be determined to be 1/2 or less of the sampling rate.

According to an embodiment, when the sampling rate is 8000 Hz, the audio bandwidth may be determined to be 0 to 4000 Hz. According to an embodiment, an audio bandwidth of 0 to 4000 Hz may be referred to as a narrowband (NB). According to an embodiment, when the sampling rate is 16000 Hz, the audio bandwidth may be determined to be 0 to 8000 Hz. According to an embodiment, an audio bandwidth of 0 to 8000 Hz may be referred to as a wideband (WB). According to an embodiment, when the sampling rate is 32000 Hz, the audio bandwidth may be determined to be 0 to 16000 Hz. According to an embodiment, an audio bandwidth of 0 to 16000 Hz may be referred to as a super-wideband (SWB). According to an embodiment, when the sampling rate is 48000 Hz, the audio bandwidth may be determined to be 0-20000 Hz. Since the human audible frequency band is 20-20000 Hz, according to an embodiment, an audio bandwidth of 0-20000 Hz may be referred to as a fullband (FB).

The buck converter of the audio electronic device according to an embodiment may be a hysteresis buck converter operating by pulse frequency modulation (PFM). According to an embodiment, when the hysteresis buck converter of the audio electronic device operates in the PFM mode, the audio electronic device may change the range of the switching frequency by changing the hysteresis threshold. According to an embodiment, the switching frequency may be a value between a first switching threshold and a second switching threshold greater than the first switching threshold. According to an embodiment, the audio electronic device may change the first switching threshold value by changing the first hysteresis threshold value, and may change the second switching threshold value by changing the second hysteresis threshold value. The audio electronic device according to an embodiment may change the first hysteresis threshold so that the switching frequency of the hysteresis buck converter is higher than the maximum frequency of the audio bandwidth.

According to an embodiment, when the audio bandwidth is determined to be narrow (0 to 4000 Hz), the audio electronic device may change the first hysteresis threshold so that the switching frequency of the hysteresis buck converter is higher than 4000 Hz, which is the maximum frequency of the audio bandwidth. can According to an embodiment, the audio electronic device may change the first hysteresis threshold so that the lowest switching frequency of the hysteresis buck converter exceeds 4000 Hz. According to an embodiment, the audio electronic device may change the first hysteresis threshold so that the switching frequency of the hysteresis buck converter is between 4000 Hz and 8000 Hz.

According to an embodiment, when the audio bandwidth is determined to be wide (0 to 8000 Hz), the audio electronic device may change the first hysteresis threshold so that the switching frequency of the hysteresis buck converter is higher than 8000 Hz, which is the maximum frequency of the audio bandwidth. have. According to an embodiment, the audio electronic device may change the first hysteresis threshold so that the lowest switching frequency of the hysteresis buck converter exceeds 8000 Hz. According to an embodiment, the audio electronic device may change the first hysteresis threshold so that the switching frequency of the hysteresis buck converter is between 8000 Hz and 16000 Hz.

According to an embodiment, when the audio bandwidth is determined to be an ultra-wide band (0 to 16000 Hz), the audio electronic device changes the first hysteresis threshold so that the switching frequency of the hysteresis buck converter is higher than 16000 Hz, which is the maximum frequency of the audio bandwidth. can According to an embodiment, the audio electronic device may change the first hysteresis threshold so that the lowest switching frequency of the hysteresis buck converter exceeds 16000 Hz. According to an embodiment, the audio electronic device may change the first hysteresis threshold so that the switching frequency of the hysteresis buck converter is between 16000 Hz and 20000 Hz.

According to an embodiment, when the audio bandwidth is determined to be the full band (0 to 20000 Hz), the audio electronic device may change the first hysteresis threshold so that the switching frequency of the hysteresis buck converter is higher than 20000 Hz, which is the maximum frequency of the audio bandwidth. have. According to an embodiment, the audio electronic device may change the first hysteresis threshold so that the lowest switching frequency of the hysteresis buck converter exceeds 20000 Hz. According to an embodiment, the audio electronic device may change the first hysteresis threshold so that the switching frequency of the hysteresis buck converter exceeds 20000 Hz.

As described above, according to an embodiment, the first switching threshold is determined based on a first hysteresis threshold of the hysteresis buck converter, and the second switching threshold is based on a second hysteresis threshold of the hysteresis buck converter. can be decided. According to an embodiment, as the audio bandwidth is determined as the first band, the audio electronic device may change the first hysteresis threshold so that the first switching threshold becomes the maximum frequency of the first band. According to an embodiment, the audio electronic device may change the second hysteresis threshold so that the second switching threshold becomes the maximum frequency of the second band. In this case, the second band may be wider than the first band.

According to an embodiment, when the first band is a narrow band (0 to 4000 Hz), the second band may be a wide band (0 to 8000 Hz). In this case, as the audio bandwidth is determined to be a narrow band (0 to 4000 Hz), the audio electronic device according to an embodiment sets the first hysteresis threshold so that the first switching threshold becomes 4000 Hz, which is the maximum frequency of the narrow band. can be changed According to an embodiment, the audio electronic device may change the second hysteresis threshold so that the second switching threshold becomes 8000 Hz, which is the maximum frequency of the broadband. Accordingly, according to an embodiment, the audio electronic device performs the first hysteresis such that the lowest switching frequency exceeds 4000 Hz and the maximum switching frequency is less than 8000 Hz, as the audio bandwidth is determined to be a narrow band (0 to 4000 Hz). You can change the threshold.

According to an embodiment, when the first band is a wide band (0 to 8000 Hz), the second band may be an ultra-wide band (0 to 16000 Hz). In this case, as the audio bandwidth is determined to be wide (0 to 8000 Hz), the audio electronic device according to an embodiment may change the first hysteresis threshold so that the first switching threshold becomes 8000 Hz, which is the maximum frequency of the wideband. have. According to an embodiment, the audio electronic device may change the second hysteresis threshold so that the second switching threshold becomes 16000 Hz, which is the maximum frequency of the ultra-wideband. Accordingly, according to an embodiment, the audio electronic device has a first hysteresis threshold such that the lowest switching frequency exceeds 8000 Hz and the maximum switching frequency is less than 16000 Hz, as the audio bandwidth is determined to be broadband (0 to 8000 Hz). You can change the value.

According to an embodiment, when the first band is an ultra-wide band (0 to 16000 Hz), the second band may be a full band (0 to 20000 Hz). In this case, the audio electronic device according to an embodiment sets the first hysteresis threshold so that the first switching threshold becomes 16000 Hz, which is the maximum frequency of the ultra-wideband, as the audio bandwidth is determined to be in the ultra-wide band (0 to 16000 Hz). can be changed According to one chamber o'clock, audio electronic device is capable of changing the second hysteresis threshold of the second switching threshold so that the 20000 Hz maximum frequency of the full-band. Accordingly, according to an embodiment, the audio electronic device performs the first hysteresis such that the lowest switching frequency exceeds 16000 Hz and the maximum switching frequency is less than 20000 Hz, as the audio bandwidth is determined to be an ultra-wide band (0 to 16000 Hz). You can change the threshold.

According to an embodiment, the first band may be a full band (0 to 20000 Hz). The audio electronic device according to an embodiment may change the first hysteresis threshold value so that the first switching threshold becomes 20000 Hz, which is the maximum frequency of the entire band, as the audio bandwidth is determined to be in the full band (0 to 20000 Hz). Accordingly, according to an embodiment, the audio electronic device may change the first hysteresis threshold so that the lowest switching frequency exceeds 20000 Hz as the audio bandwidth is determined to be the full band (0 to 20000 Hz).

In the above-described embodiment, the example in which the second switching threshold is determined based on the audio bandwidth is exemplified, but the present invention is not limited thereto. According to an embodiment, the second switching threshold may be determined based on a load condition of the audio electronic device. As described above, since the second switching threshold value may be determined based on the second hysteresis threshold value, the audio electronic device according to an embodiment changes the second hysteresis threshold value based on the load condition, thereby increasing the second switching threshold value. You can change the value.

According to an embodiment, the load condition is a USB PHY (eg, the USB PHY 120 of FIG. 1 ), an audio codec (eg, the audio codec 154 of FIG. 1 ), a digital signal processor (DSP), a memory (eg, : load conditions of at least one of RAM 142, or flash memory 144 of FIG. 1), digital core, analog core, I/O interface, and microcontroller (eg, microcontroller 130 of FIG. 1); may include

According to an embodiment, the audio electronic device may provide the switching frequency of the hysteresis buck converter in consideration of power efficiency according to the load condition by changing the second switching threshold based on the load condition of the audio electronic device.

Accordingly, in the audio electronic device according to an embodiment, the power efficiency and power efficiency and A power supply that optimizes audio performance related to noise is possible.

The buck converter of the audio electronic device according to an embodiment may be a hysteresis buck converter operating by pulse width modulation (PWM). According to an embodiment, when the hysteresis buck converter of the audio electronic device operates in the PWM mode, the audio electronic device may change a fixed switching frequency of the hysteresis buck converter. Hereinafter, when the hysteresis buck converter of the audio electronic device operates in the PWM mode according to an embodiment, a method of changing the switching frequency by the audio electronic device based on the audio bandwidth will be described.

The audio electronic device according to an embodiment may change the switching frequency so that the switching frequency of the hysteresis buck converter is higher than the maximum frequency of the audio bandwidth.

According to an embodiment, when the audio bandwidth is determined to be a narrow band (0 to 4000 Hz), the audio electronic device may change the switching frequency of the hysteresis buck converter to be higher than 4000 Hz, which is the maximum frequency of the audio bandwidth.

According to an embodiment, when the audio bandwidth is determined to be wide (0 to 8000 Hz), the audio electronic device may change the switching frequency of the hysteresis buck converter to be higher than 8000 Hz, which is the maximum frequency of the audio bandwidth.

According to an embodiment, when the audio bandwidth is determined to be an ultra-wide band (0 to 16000 Hz), the audio electronic device may change the switching frequency of the hysteresis buck converter to be higher than 16000 Hz, which is the maximum frequency of the audio bandwidth.

According to an embodiment, when the audio bandwidth is determined to be the full band (0 to 20000 Hz), the audio electronic device may change the switching frequency of the hysteresis buck converter to be higher than 20000 Hz, which is the maximum frequency of the audio bandwidth.

According to an embodiment, the audio electronic device may change the switching frequency of the hysteresis buck converter further based on a load condition of the audio electronic device. The load condition may include at least one of a USB PHY, an audio codec, a DSP, and a memory, as described above.

According to an embodiment, the audio electronic device may determine one of frequencies higher than the maximum frequency of the audio bandwidth as the switching frequency of the hysteresis buck converter based on a load condition of the audio electronic device.

According to an embodiment, the audio electronic device may remove noise in the audible frequency band due to switching while maintaining high power efficiency according to the load condition by changing the switching frequency based on the audio bandwidth and the load condition.

Hereinafter, a method of operating a hysteresis buck converter and a method of changing a switching frequency will be described with reference to FIG. 4 .

4 is a circuit diagram 400 of a hysteresis buck converter according to an embodiment. 4, the hysteresis buck converter (for example, the hysteresis buck converter 212 of FIG. 2) according to various embodiments disclosed herein includes a hysteresis window controller 410, a hysteresis comparator 420, It may include a dead time controller 430 , and a switch 440 .

According to an embodiment, the hysteresis window controller 410 may control a hysteresis threshold. According to an embodiment, the hysteresis threshold may include a first hysteresis threshold V _L and a second hysteresis threshold V _H . According to an embodiment, the hysteresis window controller 410 may generate a hysteresis window Δhyst. According to an embodiment, the hysteresis window may correspond to a difference between the second hysteresis threshold and the first hysteresis threshold (Δhyst = V _H - V _L ). According to an embodiment, the hysteresis window (Δhyst = V _H - V _L ) may be input to the hysteresis comparator 420 .

According to an embodiment, the hysteresis comparator 420 may include an input terminal and a reference voltage terminal. According to an embodiment, the feedback voltage V _f may be input to the input terminal of the hysteresis comparator 420 . According to an exemplary embodiment, the hysteresis thresholds V _H and V _L may be input to a reference voltage terminal of the hysteresis comparator 420 as a reference voltage. According to one embodiment. The hysteresis comparator 420 may compare the feedback voltage V _f provided to the input terminal with the first reference voltage V _L or the second reference voltage V _H provided to the reference voltage terminal.

According to an embodiment, when the feedback voltage V _f is higher than the second reference voltage V _H , the hysteresis comparator 420 may output a logic 'High' output Comp. According to an embodiment, when the feedback voltage V _f is lower than the first reference voltage V _L , an output of logic 'Low' may be output.

According to an embodiment, the dead time controller 430 may control the switch 440 based on the comparison result Comp output from the hysteresis comparator 420 . The switch 440 may include a pull-up switch M _P and a pull-down switch M _N . According to one embodiment, the dead-time controller 430 is a second switch for driving the first switching signal (S1) and the pull-down switch (M _N) for driving the pull-up switch (M _P) in accordance with the result of the comparison (Comp) A signal S2 may be output. According to an embodiment, the dead time controller 430 _{drives the pull-up switch M P} to an On state and the pull-down switch M _N to an Off state as the comparison result Comp is 'High'. can do it According to an embodiment, the dead time controller 430 _{drives the pull-up switch M P} to an Off state and the pull-down switch M _N to an On state as the comparison result Comp is 'Low'. can do it

According to one embodiment, the power efficiency may be reduced if the pull-up switch (M _P) and the pull-down switch (M _N) at the same time that the On state. Thus, according to one embodiment of the dead time controller 430 may generate a period-Off state the pull-up switch (M _P) and the pull-down switch (M _N) at the same time. In this case, a period in which the pull-up switch M _P and the pull-down switch M _N are simultaneously in an Off state may be referred to as a dead-time period.

The switch 440 may apply a voltage to the inductor L in response to the switching signals S1 and S2 . According to an embodiment, when the first switching signal S1 is input to the switch 440 , the pull-up switch M _P is driven in an On state, and the power supply voltage V _{in the inductor L and the output capacitor C is applied.} ) can be approved. According to an embodiment, when the second switching signal S2 is input to the switch 440 , the pull-down switch M _N is driven in an On state, and one end of the inductor L may be grounded.

According to one embodiment, the effective series resistance (R _ESR ) may be a component generated according to the connection of the output capacitor (C). According to an embodiment, the feedback resistors R ₁ and R ₂ may divide the output voltage V _{out .}

According to an embodiment, the hysteresis window controller 410 may adjust the hysteresis thresholds V _L and V _H based on the audio bandwidth. The hysteresis window controller 410 may control the hysteresis window (Δhyst = V _H - V _L ) _{by adjusting the hysteresis thresholds V L} and V _{H .} Accordingly, the hysteresis window controller 410 may adaptively control the hysteresis window Δhyst according to the audio bandwidth. According to an embodiment, as the audio bandwidth increases, the hysteresis window Δhyst may be controlled to decrease.

According to an embodiment, the switching frequency f _sw of the hysteresis buck converter may be changed according to the hysteresis window Δhyst. According to an embodiment, as the hysteresis window Δhyst decreases, the switching frequency f _sw may increase.

Accordingly, according to an embodiment, the hysteresis window controller 410 may variably change the switching frequency fsw of the hysteresis buck converter by changing the _{hysteresis thresholds V L} and V _{H based on the audio bandwidth.} .

Hereinafter, with reference to FIG. 5 , the audio electronic device disclosed in this document (eg, the audio electronic device 201 of FIG. 2 ) changes the hysteresis threshold of the hysteresis buck converter (hysteresis buck converter 212 of FIG. 2 ). A method of reducing noise in the audible frequency band (f _AudibleL or more and f _AudibleH or less) will be described. In this case, the audible frequency band (f _AudibleL or more and f _AudibleH or less) may mean a band corresponding to an audio bandwidth determined according to a sampling rate. According to an embodiment, when the audio bandwidth is determined to be a narrowband, f _AudibleL may be 0 Hz and f _AudibleH may be 4000 Hz.

5 is a diagram 500 illustrating a method of reducing audio noise according to a change in a hysteresis threshold of an audio electronic device according to an exemplary embodiment. _{FIG. 5A is a diagram illustrating a switching frequency f sw} of a hysteresis buck converter before the audio electronic device changes a hysteresis threshold according to an embodiment, and FIG. 5B is a diagram according to an embodiment It is a diagram illustrating _{the switching frequency f sw} of the hysteresis buck converter after the audio electronic device changes the hysteresis threshold.

According to an embodiment, the hysteresis buck converter of the audio electronic device may operate by pulse frequency modulation. According to an embodiment, the audio electronic device may change the range of _{the switching frequency f sw by changing the hysteresis threshold.} According to an embodiment _{, the range of the switching frequency f sw} may be defined by a first switching threshold value and a second switching threshold value.

According to an embodiment, the switching frequency f _sw of the hysteresis buck converter may be between the first switching threshold value f _swThVL and the second switching threshold value f _swThVH . At this time, the first switching threshold value (f _swThVL) may represent a value less than a second switching threshold (f _swThVH).

Referring to FIG. 5A , before the audio electronic device changes the hysteresis threshold, the switching frequency f _sw of the hysteresis buck converter may be included in the audible frequency band (f _AudibleL or more and f _AudibleH or less). In other words, the first switching threshold f _swThVL may be greater than or equal to the lowest frequency of the audible frequency band, and the second switching threshold f _swThVH may be less than or equal to the maximum frequency of the audible frequency band. In this case, _{audio noise (switching noise) generated at the switching frequency f sw} may be recognized by a user of the audio electronic device.

Referring to (b) of Figure 5, the audio electronic apparatus includes a first hysteresis threshold to be higher than the maximum frequency (f _AudibleH) of the switching frequency (f _sw) is the audio frequency band (f _AudibleL than f _AudibleH or less) of the hysteretic buck converter You can change the value. According to an embodiment, the audio electronic device may change the first hysteresis threshold so _{that the first switching threshold f swThVL is equal} to or greater than the maximum frequency f AudibleH of the audible frequency band. According to an embodiment, after the audio electronic device changes the first hysteresis threshold, the switching frequency f _sw of the hysteresis buck converter may be out of the audible frequency band. In this case, _{audio noise (switching noise) generated at the switching frequency f sw} may not be recognized by the user of the audio electronic device because it is filtered by the audio codec or encoder.

Table 1 below is a table illustrating a lookup table of the switching frequency of the first switching threshold and the hysteresis buck converter according to the sampling rate and the audio bandwidth.

Referring to Table 1, as the sampling rate is 8 kHz, the audio bandwidth may be determined as a narrowband. When the audio bandwidth is determined to be narrow, f _AudibleL may be 0 Hz, and f _AudibleH may be 4 kHz. In this case, the audio electronic device according to an embodiment may change the first hysteresis threshold value such that the first switching threshold value is 4 kHz. _{The audio electronic device may change the range of the switching frequency f sw} of the hysteresis buck converter to, for example, greater than 4 kHz and less than 8 kHz by changing the first hysteresis threshold such that the first switching threshold is 4 kHz. . That is, the switching frequency f _sw of the hysteresis buck converter may be higher than 4 kHz, which is the maximum frequency of the audio bandwidth determined as a narrowband. According to an embodiment, as the sampling rate is 16 kHz, the audio bandwidth is wideband). When the audio bandwidth is determined to be wide, f _AudibleL may be 0 Hz, and f _AudibleH may be 8 kHz. In this case, the audio electronic device according to an embodiment may change the first hysteresis threshold so that the first switching threshold is 8 kHz. _{The audio electronic device may change the range of the switching frequency f sw} of the hysteresis buck converter to, for example, greater than 8 kHz and less than 16 kHz by changing the first hysteresis threshold so that the first switching threshold is 8 kHz. . That is, the switching frequency f _sw of the hysteresis buck converter may be higher than 8 kHz, which is the maximum frequency of the audio bandwidth determined as a broadband.

According to an embodiment, as the sampling rate is 32 kHz, the audio bandwidth may be determined to be super-wideband. When the audio bandwidth is determined to be ultra-wide, f _AudibleL may be 0 Hz and f _AudibleH may be 16 kHz. In this case, the audio electronic device according to an embodiment may change the first hysteresis threshold value such that the first switching threshold value is 16 kHz. _{The audio electronic device may change the range of the switching frequency f sw} of the hysteresis buck converter to, for example, greater than 16 kHz and less than 20 kHz by changing the first hysteresis threshold so that the first switching threshold is 16 kHz. . That is, the switching frequency f _sw of the hysteresis buck converter may be higher than 16 kHz, which is the maximum frequency of the audio bandwidth determined as the ultra-wideband.

According to an embodiment, as the sampling rate is 44.1 kHz or 48 kHz, the audio bandwidth may be determined to be fullband. When the audio bandwidth is determined for the full band, f _AudibleL may be 0 Hz, and f _AudibleH may be 20 kHz. In this case, the audio electronic device according to an embodiment may change the first hysteresis threshold value such that the first switching threshold value is 20 kHz. _{The audio electronic device may change the range of the switching frequency f sw} of the hysteresis buck converter to be greater than, for example, 20 kHz by changing the first hysteresis threshold so that the first switching threshold is 20 kHz. That is, the switching frequency f _sw of the hysteresis buck converter may be higher than 20 kHz, which is the maximum frequency of the audio bandwidth determined by the full band.

According to an embodiment, the audio electronic device adjusts the range of the switching frequency of the hysteresis buck converter by changing the first hysteresis threshold based on the audio bandwidth, thereby removing audio noise that can be heard by the user according to the switching of the hysteresis buck converter. It is possible to reduce noise in the audible frequency band.

In the above-described embodiment, the case where the hysteresis buck converter operates by pulse frequency modulation is taken as an example, but the hysteresis buck converter may operate by pulse width modulation. According to an embodiment, when the hysteresis buck converter operates with pulse width modulation, the switching frequency of the hysteresis buck converter may be fixed. The audio electronic device according to an embodiment may change the fixed switching frequency of the hysteresis buck converter so that the fixed switching frequency is out of an audible frequency band. That is, the audio electronic device according to an embodiment may remove noise due to switching of the hysteresis buck converter by changing the switching frequency of the hysteresis buck converter based on the audio bandwidth.

Hereinafter, with reference to FIG. 6 , audio noise in an audible frequency band according to a switching frequency of a hysteresis buck converter (eg, the hysteresis buck converter 212 of FIG. 2 ) disclosed in this document is compared and described. In this case, the audible frequency band may refer to a human audible frequency band of 20 Hz or more and 20 kHz or less.

6 is a diagram 600 illustrating a change in audio noise according to a change in a switching frequency of a hysteresis buck converter according to an embodiment. In FIG. 6 , a first signal 601 represents a fast Fourier transformed signal of a recorded sound source when the switching frequency of the hysteresis buck converter is 19 kHz, and a second signal 602 is the hysteresis buck converter When the switching frequency is 49 kHz, it represents the fast Fourier transformed signal of the recorded sound source.

Referring to FIG. 6 , when the switching frequency of the hysteresis buck converter is included in the audible frequency band (in the case of the first signal 601), audio noise due to switching at the switching frequency (19 kHz) is relatively large. can confirm. On the other hand, when the switching frequency of the hysteresis buck converter is higher than the maximum frequency of the audible frequency band (the second signal 602), it can be confirmed that audio noise does not occur due to switching at the switching frequency (49 kHz). have.

Accordingly, when the audio electronic device according to an embodiment changes the switching frequency of the hysteresis buck converter to be higher than the maximum frequency of the audible frequency band, audio noise in the audible frequency band may be reduced.

Also, since the audio electronic device filters the audio signal according to the audio bandwidth, audio noise higher than the maximum frequency of the audio bandwidth may be removed by the filter. Accordingly, the audio electronic device according to an embodiment may remove audio noise due to switching by changing the switching frequency of the hysteresis buck converter to be higher than the maximum frequency of the audio bandwidth.

Hereinafter, a method for determining an audio bandwidth disclosed in this document will be described with reference to FIG. 7 .

7 is a diagram 700 illustrating an example of an audio bandwidth according to an audio codec or a sampling rate. Referring to FIG. 7 , an audio bandwidth may be determined according to a sampling rate and/or an audio codec.

As described above, the audio bandwidth may be determined based on a sampling rate supported by the audio electronic device (eg, the audio electronic device 101 of FIG. 1 ). The method of determining the sampling rate may be the same as the method of the embodiment described above with reference to FIG. 3 .

For example, referring to FIG. 7 , if the sampling rate is 8000 Hz, the audio bandwidth may be determined to be narrowband (NB). Accordingly, the audio electronic device may change the switching frequency or the range of the switching frequency so that the switching frequency of the hysteresis buck converter is higher than 4000 Hz, which is the maximum frequency of the narrow band (0 to 4000 Hz). Alternatively, according to an embodiment, a sampling rate may be determined according to an audio codec supported by the audio electronic device, and an audio bandwidth may be determined according to the sampling rate. That is, a sampling rate and an audio bandwidth may be determined according to an audio codec.

For example, referring to FIG. 7 , if the audio codec is SBC, the sampling rate may be determined to be 48000 Hz. In this case, the audio bandwidth may be determined to be fullband (FB). Accordingly, the audio electronic device may change the switching frequency or the range of the switching frequency so that the switching frequency of the hysteresis buck converter is higher than 20000 Hz, which is the maximum frequency of the full band (0-20000 Hz).

According to an embodiment, when the audio electronic device is connected to the external electronic device through a wired communication circuit (eg, USB), the audio bandwidth may be determined based on at least one sampling rate supported by the audio electronic device.

Alternatively, according to an embodiment, in the case of an audio electronic device connected to an external electronic device based on a wireless connection (eg, a Bluetooth communication connection), a sampling rate and an audio bandwidth may be determined based on an audio codec supported by the audio electronic device. and will be described below

Hereinafter, a configuration of an audio electronic device according to another exemplary embodiment will be described with reference to FIG. 8 .

8 is a block diagram 800 of an audio electronic device according to another embodiment. According to an embodiment, the audio electronic device 801 may be a Bluetooth headset, but is not limited thereto, and may include various Bluetooth audio accessory devices such as a Bluetooth earphone or a Bluetooth speaker.

Referring to FIG. 8 , the audio electronic device 801 according to an embodiment includes a power circuit 810 , a Bluetooth communication circuit 820 , a microcontroller 830 , a RAM 842 , a flash memory 844 , and an audio DMA. It may include a controller 852 , an audio codec 854 , a peripheral device 860 , and a system bus matrix 890 . According to an embodiment, the power circuit 810 may include a hysteresis buck converter 812 and a linear regulator 814 .

Meanwhile, in the audio electronic device 801 shown in FIG. 8 , among the configurations of the audio electronic device 101 shown in FIG. 1 , a configuration having the same name as that of the audio electronic device 101 shown in FIG. 1 corresponds to each other. Since it corresponds to the configuration, a detailed description will be omitted in relation to the corresponding configuration, and a configuration with a difference will be described.

According to an embodiment, the audio electronic device 801 may be connected to the external electronic device 802 by the Bluetooth communication circuit 820 . In this case, the external electronic device 802 may also include a Bluetooth communication circuit 880 . According to an exemplary embodiment, the external electronic device 802 is a portable communication device (eg, a smartphone), a computer device (eg, a personal digital assistant (PDA), a tablet PC), or a laptop PC (eg, a desktop PC, a workstation). , or a server), a portable multimedia device (eg, an e-book reader or an MP3 player), or a wearable device.

According to an embodiment, the audio electronic device 801 is a hands-free device (or a sink device), and the external electronic device 802 connected thereto through Bluetooth is an audio gateway. It may be a device (or a source device). According to an embodiment, the Bluetooth communication circuit 820 of the audio electronic device 801 may provide a hands free profile (HFP). Accordingly, the audio electronic device 801 according to an embodiment may transmit or receive a command or data based on the HFP and the external electronic device 802 .

Hereinafter, an operation of the audio electronic device (eg, the audio electronic device 801 of FIG. 8 ) according to an embodiment that provides the Bluetooth protocol will be described with reference to FIG. 9 . The operation of the audio electronic device described with reference to FIG. 9 may be performed by the microcontroller 830 of FIG. 8 .

9 is a flowchart 900 illustrating a method of operating an audio electronic device according to an exemplary embodiment. Specifically, FIG. 9 is a diagram illustrating a method for an audio electronic device to change a switching frequency of a buck converter (eg, the hysteresis buck converter 812 of FIG. 8 ).

Referring to FIG. 9 , in operation 901 , the audio electronic device according to an embodiment may be wirelessly connected to an external electronic device (eg, the external electronic device 802 of FIG. 8 ) by a communication circuit. According to an embodiment, the communication circuit of the audio electronic device may include a communication circuit that provides a Bluetooth protocol (eg, the Bluetooth communication circuit 820 of FIG. 8 ). In this case, the communication circuit of the external electronic device may also include a communication circuit providing a Bluetooth protocol (eg, the Bluetooth communication circuit 880 of FIG. 8 ).

In operation 902, the audio electronic device according to an embodiment may determine the audio codec by performing audio codec negotiation with the external electronic device. Hereinafter, audio codec negotiation will be described in detail.

According to an embodiment, the audio electronic device may receive the first audio codec from an external electronic device paired with the external electronic device. According to an embodiment, when the first audio codec is available, the audio electronic device may transmit an “OK” response to the external electronic device. In this case, the audio electronic device may determine the first audio codec as the audio codec. According to an embodiment, when the first audio codec is unavailable to the audio electronic device, the audio electronic device may transmit the available second audio codec to the external electronic device and determine the second audio codec as the audio codec. Meanwhile, according to an embodiment, the audio codec may be included in information related to conversion of an audio signal.

In operation 903, the audio electronic device according to an embodiment may change the switching frequency of the buck converter (eg, the hysteresis buck converter 812 of FIG. 8 ) based on at least a part of information related to conversion of an audio signal. As described above, the information related to the conversion of the audio signal may include at least one of an audio codec, an audio bandwidth, and a sampling rate. According to an embodiment, the audio electronic device may change the switching frequency of the buck converter based on a sampling rate and an audio bandwidth determined according to an audio codec. Meanwhile, operation 903 of FIG. 9 is an operation of changing the switching frequency of the buck converter based on the audio bandwidth, and may correspond to operation 303 of FIG. 3 . Accordingly, the description described above with respect to operation 303 with reference to FIG. 3 may be equally applied to operation 903 .

An audio codec may be different according to a Bluetooth profile provided by a communication circuit of an audio electronic device, and as described with reference to FIG. 7 , a sampling rate and an audio bandwidth may be determined according to the audio codec. For example, as the communication circuit of the audio electronic device provides the HFP, the audio codec may be mSBC. In this case, the sampling rate may be determined to be 16000 Hz, and the audio bandwidth may be determined to be a broadband of 8000 Hz or less.

The buck converter of the audio electronic device according to an embodiment may be a hysteresis buck converter operating by pulse frequency modulation (PFM). According to an embodiment, when the hysteresis buck converter of the audio electronic device operates in the PFM mode, the audio electronic device may change the range of the switching frequency by changing the hysteresis threshold. According to an embodiment, the switching frequency may be a value between a first switching threshold and a second switching threshold greater than the first switching threshold. According to an embodiment, the audio electronic device may change the first switching threshold value by changing the first hysteresis threshold value, and may change the second switching threshold value by changing the second hysteresis threshold value.

According to an embodiment, the audio electronic device may change the first hysteresis threshold so that the switching frequency of the hysteresis buck converter is higher than the maximum frequency of the audio bandwidth determined according to the audio codec.

According to an embodiment, when the audio bandwidth is determined to be wide (0 to 8000 Hz), the audio electronic device changes the first hysteresis threshold so that the switching frequency of the hysteresis buck converter is higher than 8000 Hz, which is the maximum frequency of the audio bandwidth. can

As described above, according to an embodiment, the first switching threshold may be determined based on the first hysteresis threshold, and the second switching threshold may be determined based on the second hysteresis threshold.

According to an embodiment, as the audio bandwidth is determined as the first band, the first hysteresis threshold may be changed such that the first switching threshold becomes the maximum frequency of the first band. According to an embodiment, the audio electronic device may change the second hysteresis threshold so that the second switching threshold becomes the maximum frequency of the second band. In this case, the second band may be wider than the first band.

According to an embodiment, as the audio bandwidth is determined to be wide (0 to 8000 Hz), the first hysteresis threshold may be changed such that the first switching threshold is 8000 Hz. According to an embodiment, the audio electronic device may change the second hysteresis threshold so that the second switching threshold becomes 16000 Hz, which is the maximum frequency of the ultra-wideband. Accordingly, according to an embodiment, the audio electronic device has a first hysteresis threshold such that the lowest switching frequency exceeds 8000 Hz and the maximum switching frequency is less than 16000 Hz, as the audio bandwidth is determined to be broadband (0 to 8000 Hz). You can change the value.

In the above-described embodiment, the case where the audio bandwidth is determined to be broadband (0 to 8000 Hz) is exemplified, but the present invention is not limited thereto. and changing the second hysteresis threshold to change the first switching threshold and the second switching threshold.

In the above-described embodiment, the example in which the second switching threshold is determined based on the audio bandwidth is exemplified, but the present invention is not limited thereto. According to an embodiment, the second switching threshold may be determined based on a load condition of the audio electronic device.

According to an embodiment, the audio electronic device may change the second switching threshold by changing the second hysteresis threshold based on a load condition. According to an embodiment, the load condition may be an audio codec (eg, the audio codec 854 of FIG. 8 ), a digital signal processor (DSP), or a memory (eg, the RAM 842 or the flash memory 844 of FIG. 8 ). , a digital core, an analog core, an I/O interface, and a load condition of at least one of a microcontroller (eg, the microcontroller 830 of FIG. 8 ).

Accordingly, the audio electronic device according to an embodiment adjusts the first hysteresis threshold value and the second hysteresis threshold value to change the first switching threshold value and the second switching threshold value to adjust the switching frequency, thereby providing a load condition In addition to maximizing power efficiency according to

The buck converter of the audio electronic device according to an embodiment may be a hysteresis buck converter operating by pulse width modulation (PWM). According to an embodiment, when the hysteresis buck converter of the audio electronic device operates in the PWM mode, the audio electronic device may change a fixed switching frequency of the hysteresis buck converter. Hereinafter, when the hysteresis buck converter of the audio electronic device operates in the PWM mode according to an embodiment, a method of changing the switching frequency by the audio electronic device based on the audio bandwidth will be described.

According to an embodiment, the audio electronic device may change the switching frequency of the hysteresis buck converter to be higher than the maximum frequency of the audio bandwidth determined according to the audio codec.

According to an embodiment, when the audio bandwidth is determined to be wide (0 to 8000 Hz), the audio electronic device may change the switching frequency of the hysteresis buck converter to be higher than 8000 Hz, which is the maximum frequency of the audio bandwidth.

In the above embodiment, the case where the audio bandwidth is determined to be wide (0 to 8000 Hz) is taken as an example, but the present invention is not limited thereto, and the audio electronic device may change the switching frequency based on the audio bandwidth determined according to the audio codec. have.

According to an embodiment, the audio electronic device may change the switching frequency of the hysteresis buck converter further based on a load condition of the audio electronic device. The load condition may include at least one of a USB PHY, an audio codec, a DSP, and a memory, as described above.

According to an embodiment, the audio electronic device may determine one of frequencies higher than the maximum frequency of the audio bandwidth as the switching frequency of the hysteresis buck converter based on a load condition of the audio electronic device.

According to an embodiment, the audio electronic device may remove noise in the audible frequency band due to switching while maintaining high power efficiency according to the load condition by changing the switching frequency based on the audio bandwidth and the load condition.

In the embodiment described above with reference to FIGS. 8 and 9 , the case where the audio electronic device 801 communicates with the external electronic device 802 based on HFP is exemplified, but the present invention is not limited thereto. The electronic device 801 may communicate with the external electronic device 802 based on a handset profile (HSP) and an advanced audio distribution profile (A2DP).

An audio electronic device (eg, the audio electronic device 101 of FIG. 1 , the audio electronic device 201 of FIG. 2 , or the audio electronic device 801 of FIG. 8 ) according to an embodiment disclosed in this document is a buck converter (buck converter) including a power circuit (eg, the power circuit 210 of FIG. 2 ), a communication circuit (eg, the communication circuit 220 of FIG. 2 ), the power circuit (eg, the power circuit 210 of FIG. 2 ) )) and at least one processor (eg, processor 230 in FIG. 2 ) operatively connected with the communication circuit (eg, communication circuit 220 in FIG. 2 ), and the at least one processor (eg, communication circuit 220 in FIG. 2 ) a memory (eg, the memory 240 of FIG. 2 ) operatively coupled to the processor 230 of the A processor (eg, the processor 230 of FIG. 2 ) is an external electronic device (eg, the external electronic device 102 of FIG. 1 ) connected by the communication circuit (eg, the communication circuit 220 of FIG. 2 ), or FIG. Receives information related to conversion of an audio signal, including at least one of an audio codec, an audio bandwidth, and a sampling rate, from the external electronic device 802 of FIG. One or more instructions for changing the switching frequency of the buck converter based on at least a part of information related to conversion may be stored.

According to an embodiment disclosed in this document, the buck converter is a hysteresis buck converter (eg, the hysteresis buck converter 112 of FIG. 1 , the hysteresis of FIG. 2 ) operating by pulse frequency modulation. The buck converter 212 or the hysteresis buck converter 812 of FIG. 8 ), and the instructions are configured such that the processor (eg, the processor 230 of FIG. 2 ) generates the hysteresis buck converter (eg, the hysteresis buck of FIG. 1 ). The first hysteresis threshold may be changed such that the switching frequency of the converter 112, the hysteresis buck converter 212 of FIG. 2, or the hysteresis buck converter 812 of FIG. 8 is higher than the maximum frequency of the audio bandwidth. have.

According to an embodiment disclosed in this document, the switching of the hysteresis buck converter (eg, the hysteresis buck converter 112 of FIG. 1 , the hysteresis buck converter 212 of FIG. 2 , or the hysteresis buck converter 812 of FIG. 8 ) the frequency is a value between a first switching threshold and a second switching threshold greater than the first switching threshold, wherein the first switching threshold is determined based on the first hysteresis threshold, the second switching threshold The value may be determined based on the second hysteresis threshold.

According to an embodiment disclosed in this document, the instructions, when the processor (eg, the processor 230 of FIG. 2 ) determines that the audio bandwidth is the first band, the first switching threshold is the second The first hysteresis threshold may be changed so as to be the maximum frequency of one band.

According to an embodiment disclosed in this document, the instructions may cause the processor (eg, the processor 230 of FIG. 2 ) to set the second hysteresis threshold so that the second switching threshold becomes the maximum frequency of a second band. , and the second band may be wider than the first band.

According to an embodiment disclosed in this document, the second switching threshold is the audio electronic device (eg, the audio electronic device 101 of FIG. 1 , the audio electronic device 201 of FIG. 2 , or the audio device of FIG. 8 ). It may be determined based on a load condition of the electronic device 801).

According to an embodiment disclosed in this document, the instructions may be configured by the processor (eg, the processor 230 of FIG. 2 ), the audio electronic device (eg, the audio electronic device 101 of FIG. 1 ), or the audio electronic device of FIG. 2 . Information including at least one sampling rate supported by the audio electronic device 201 may be transmitted to the external electronic device (eg, the external electronic device 102 of FIG. 1 ).

According to an embodiment disclosed in this document, the sampling rate received from the external electronic device (eg, the external electronic device 102 of FIG. 1 ) is the audio electronic device (eg, the audio electronic device 101 of FIG. 1 ). , or at least one sampling rate supported by the audio electronic device 201 of FIG. 2 ) may be selected by the external electronic device (eg, the external electronic device 102 of FIG. 1 ).

According to an embodiment disclosed in this document, the buck converter is a hysteresis buck converter (eg, the hysteresis buck converter 112 of FIG. 1 , the hysteresis buck converter 212 of FIG. 2 ) operating by pulse width modulation. , or the hysteresis buck converter 812 of FIG. 8 ), and the instructions include the processor (eg, the processor 230 of FIG. 2 ), the hysteresis buck converter (eg, the hysteresis buck converter 112 of FIG. 1 ), The switching frequency of the hysteresis buck converter 212 of FIG. 2 or the hysteresis buck converter 812 of FIG. 8 may be changed to be higher than the maximum frequency of the audio bandwidth.

The audio electronic device (eg, the audio electronic device 201 of FIG. 2 or the audio electronic device 801 of FIG. 8 ) according to an embodiment disclosed in this document includes the communication circuit (eg, the audio electronic device of FIG. 2 ) 220 ) is configured to provide a Bluetooth protocol, and the instructions include the processor (eg, processor 230 in FIG. 2 ) connected by the communication circuit (eg, communication circuit 220 in FIG. 2 ). The audio codec may be determined by performing audio codec negotiation with an external electronic device (eg, the audio electronic device 201 of FIG. 2 or the audio electronic device 802 of FIG. 8 ).

According to an embodiment disclosed in this document, an audio electronic device including a buck converter (eg, the audio electronic device 101 of FIG. 1 , the audio electronic device 201 of FIG. 2 , or the audio electronic device 801 of FIG. 8 ) )) of the audio electronic device (eg, the audio electronic device 101 of FIG. 1 , the audio electronic device 201 of FIG. 2 ) by a communication circuit (eg, the communication circuit 220 of FIG. 2 ). or an audio codec and audio bandwidth from an external electronic device (the external electronic device 102 of FIG. 1 or the external electronic device 802 of FIG. 8 ) connected to the audio electronic device 801 of FIG. 8 ). And changing the switching frequency of the buck converter based on at least a part of the operation of receiving information related to the conversion of the audio signal, including at least one of a sampling rate, and the information related to the conversion of the audio signal. It can include actions.

According to an embodiment disclosed in this document, the buck converter is a hysteresis buck converter (eg, the hysteresis buck converter 112 of FIG. 1 , the hysteresis of FIG. 2 ) operating by pulse frequency modulation. The buck converter 212 or the hysteresis buck converter 812 of FIG. 8 ), and the operation of changing the switching frequency is the hysteresis buck converter (eg, the hysteresis buck converter 112 of FIG. 1 , the hysteresis buck of FIG. 2 ) and changing the first hysteresis threshold so that the switching frequency of the converter 212 or the hysteresis buck converter 812 of FIG. 8 is higher than the maximum frequency of the audio bandwidth.

According to an embodiment disclosed in this document, the switching of the hysteresis buck converter (eg, the hysteresis buck converter 112 of FIG. 1 , the hysteresis buck converter 212 of FIG. 2 , or the hysteresis buck converter 812 of FIG. 8 ) the frequency is a value between a first switching threshold and a second switching threshold greater than the first switching threshold, wherein the first switching threshold is determined based on the first hysteresis threshold, the second switching threshold The value may be determined based on the second hysteresis threshold.

According to an embodiment disclosed in this document, the changing of the first hysteresis threshold may include, as the audio bandwidth is determined as the first band, such that the first switching threshold becomes the maximum frequency of the first band. and determining the first hysteresis threshold.

According to an embodiment disclosed in this document, the operation of changing the second hysteresis threshold includes changing the second hysteresis threshold so that the second switching threshold becomes the maximum frequency of a second band, and , the second band may be wider than the first band.

According to an embodiment disclosed in this document, the second switching threshold is the audio electronic device (eg, the audio electronic device 101 of FIG. 1 , the audio electronic device 201 of FIG. 2 , or the audio device of FIG. 8 ). It may be determined based on a load condition of the electronic device 801).

According to an embodiment disclosed in this document, the method of operating an audio electronic device (eg, the audio electronic device 101 of FIG. 1 or the audio electronic device 201 of FIG. 2 ) including the buck converter includes the audio At least one sampling rate supported by the audio electronic device (eg, the audio electronic device 101 of FIG. 1 or the audio electronic device 201 of FIG. 2 ) is included before the operation of receiving information related to signal conversion information connected to the audio electronic device (eg, the audio electronic device 101 of FIG. 1 or the audio electronic device 201 of FIG. 2 ) by the communication circuit (eg, the communication circuit 220 of FIG. 2 ) The operation of transmitting to an external electronic device (eg, the external electronic device 102 of FIG. 1 ) may be further included.

According to an embodiment disclosed in this document, the sampling rate is at least one sampling supported by the audio electronic device (eg, the audio electronic device 101 of FIG. 1 or the audio electronic device 201 of FIG. 2 ). It may be a sampling rate selected by the external electronic device (eg, the external electronic device 102 of FIG. 1 ) from among the rates.

According to an embodiment disclosed in this document, the buck converter is a hysteresis buck converter (eg, the hysteresis buck converter 112 of FIG. 1 , the hysteresis buck converter 212 of FIG. 2 ) operating by pulse width modulation. , or the hysteresis buck converter 812 of FIG. 8), and the operation of changing the switching frequency includes the hysteresis buck converter (eg, the hysteresis buck converter 112 of FIG. 1 , the hysteresis buck converter 212 of FIG. 2 , Alternatively, the operation may include changing the switching frequency of the hysteresis buck converter 812 of FIG. 8 to be higher than the maximum frequency of the audio bandwidth.

According to an embodiment disclosed in this document, the method of operating an audio electronic device (eg, the audio electronic device 201 of FIG. 2 or the audio electronic device 801 of FIG. 8 ) including the buck converter includes the communication circuitry (eg, communication circuitry 220 of FIG. 2 ) is configured to provide a Bluetooth protocol, and is configured to provide the audio electronic device (eg, audio of FIG. 2 ) by the communication circuitry (eg, communication circuitry 220 of FIG. 2 ). An audio codec through audio codec negotiation with the electronic device 201 or an external electronic device (eg, the external electronic device 802 of FIG. 8 ) connected to the electronic device 201 or, for example, the audio electronic device 801 of FIG. 8 ). It may further include an operation of determining

Claims (20)

An audio electronic device comprising:
a power supply circuit including a buck converter;
communication circuit;
at least one processor operatively coupled to the power circuit and the communication circuit; and
a memory operatively coupled to the at least one processor;
The memory, when executed, the at least one processor,
Receiving information related to conversion of an audio signal, including at least one of an audio codec, an audio bandwidth, and a sampling rate, from an external electronic device connected by the communication circuit,
An electronic device for storing one or more instructions for changing a switching frequency of the buck converter based on at least a part of information related to the conversion of the audio signal. The method according to claim 1,
The buck converter is a hysteresis buck converter that operates with pulse frequency modulation,
The instructions, the processor,
and change a first hysteresis threshold such that a switching frequency of the hysteresis buck converter is higher than a maximum frequency of the audio bandwidth. 3. The method according to claim 2,
a switching frequency of the hysteresis buck converter is a value between a first switching threshold and a second switching threshold greater than the first switching threshold;
The electronic device of claim 1, wherein the first switching threshold is determined based on the first hysteresis threshold, and the second switching threshold is determined based on a second hysteresis threshold. 4. The method according to claim 3,
The instructions, the processor,
and change the first hysteresis threshold so that the first switching threshold becomes a maximum frequency of the first band as the audio bandwidth is determined as the first band. 5. The method according to claim 4,
The instructions, the processor,
change the second hysteresis threshold value so that the second switching threshold value becomes a maximum frequency of a second band;
The second band is a band wider than the first band. 4. The method according to claim 3,
The second switching threshold is,
The electronic device is determined based on a load condition of the audio electronic device. The method according to claim 1,
The instructions, the processor,
and transmit information including at least one sampling rate supported by the audio electronic device to the external electronic device. 8. The method of claim 7,
The sampling rate received from the external electronic device is selected by the external electronic device from among at least one sampling rate supported by the audio electronic device. The method according to claim 1,
The buck converter is a hysteresis buck converter operating with pulse width modulation,
The instructions, the processor,
and change a switching frequency of the hysteresis buck converter to be higher than a maximum frequency of the audio bandwidth. The method according to claim 1,
wherein the communication circuitry is configured to provide a Bluetooth protocol;
The instructions allow the processor to
and to determine the audio codec by performing audio codec negotiation with the external electronic device connected by the communication circuit. A method of operating an audio electronic device including a buck converter, the method comprising:
Receiving information related to conversion of an audio signal, including at least one of an audio codec, an audio bandwidth, and a sampling rate, from an external electronic device connected to the audio electronic device by a communication circuit ; and
and changing a switching frequency of the buck converter based on at least a part of information related to the conversion of the audio signal. 12. The method of claim 11,
The buck converter is a hysteresis buck converter that operates with pulse frequency modulation,
The operation of changing the switching frequency is,
and changing a first hysteresis threshold so that a switching frequency of the hysteresis buck converter is higher than a maximum frequency of the audio bandwidth. 13. The method of claim 12,
a switching frequency of the hysteresis buck converter is a value between a first switching threshold and a second switching threshold greater than the first switching threshold;
The method of claim 1 , wherein the first switching threshold is determined based on the first hysteresis threshold, and the second switching threshold is determined based on a second hysteresis threshold. 14. The method of claim 13,
The operation of changing the first hysteresis threshold includes:
and determining the first hysteresis threshold so that the first switching threshold becomes the maximum frequency of the first band as the audio bandwidth is determined as the first band. 15. The method of claim 14,
The operation of changing the second hysteresis threshold value comprises:
changing the second hysteresis threshold so that the second switching threshold becomes the maximum frequency of a second band;
The method of claim 1, wherein the second band is wider than the first band. 14. The method of claim 13,
The second switching threshold is,
The method of operating an audio electronic device, which is determined based on a load condition of the audio electronic device. 12. The method of claim 11,
Before the operation of receiving information related to the conversion of the audio signal,
and transmitting information including at least one sampling rate supported by the audio electronic device to an external electronic device connected to the audio electronic device by the communication circuit. 18. The method of claim 17,
The sampling rate is
and a sampling rate selected by the external electronic device from among at least one sampling rate supported by the audio electronic device. 12. The method of claim 11,
The buck converter is a hysteresis buck converter operating with pulse width modulation,
The operation of changing the switching frequency is,
and changing a switching frequency of the hysteresis buck converter to be higher than a maximum frequency of the audio bandwidth. 12. The method of claim 11,
wherein the communication circuitry is configured to provide a Bluetooth protocol;
and determining an audio codec through audio codec negotiation with an external electronic device connected to the audio electronic device by the communication circuit.

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