Electronic device comprising PFC circuit, and control method thereof

Abstract

An electronic device is disclosed. The electronic device comprises: a first PFC circuit; a second PFC circuit that is connected in parallel to the first PFC circuit; and a control circuit that controls the first PFC circuit by detecting whether a load is connected and applying a first signal for controlling on-off of the first PFC circuit to a first switch in the first PFC circuit, and controls the second PFC circuit by applying a second signal for controlling on-off of the second PFC circuit to a second switch in the second PFC circuit.

Description

Electronic device including PFC circuit and control method thereof

[0001] The present invention relates to an electronic device and a control method thereof, and more particularly, to an electronic device for controlling a burst mode of a PFC circuit and a control method thereof.

[0002] Various types of electronic devices are being developed and distributed, and in particular, recently, thin display devices for aesthetic purposes and display devices that output images through large screens are being developed and distributed.

[0003] It has been difficult to make electronic devices thin while outputting large amounts of power and to satisfy standards (or regulations) related to standby power.

[0004] In particular, conventional electronic devices including multiple PFC circuits to output a large amount of power have a problem in that they do not satisfy the standards related to standby power due to switching signals (or switching currents) when the multiple PFC circuits operate in burst mode.

[0005] There has been a demand for electronic devices that can satisfy standby power regulations when operating in standby mode and output large amounts of power when operating in normal mode.

[0006] According to one embodiment for achieving the above-described object of the present disclosure, an electronic device includes a first PFC circuit, a second PFC circuit connected in parallel with the first PFC circuit, and a control circuit for detecting whether a load is connected, applying a first signal for controlling on-off of the first PFC circuit to a first switch in the first PFC circuit to control the first PFC circuit, and applying a second signal for controlling on-off of the second PFC circuit to a second switch in the second PFC circuit to control the second PFC circuit, wherein the control circuit controls the first PFC circuit and the second PFC circuit so that output voltages of each of the first PFC circuit and the second PFC circuit correspond to a reference voltage when the connection of the load is not detected, and the reference voltage is less than an AC rectified voltage of the electronic device.

[0007] According to one embodiment for achieving the above-described object of the present disclosure, a method for controlling an electronic device including a first PFC (power factor correction) circuit and a second PFC circuit includes the steps of detecting whether a load is connected, and the steps of controlling the first PFC circuit by applying a first signal for controlling on-off of the first PFC circuit to a first switch in the first PFC circuit based on whether the load is connected, and controlling the second PFC circuit by applying a second signal for controlling on-off of the second PFC circuit to a second switch in the second PFC circuit, wherein the controlling step includes the step of controlling the first PFC circuit and the second PFC circuit so that an output voltage of each of the first PFC circuit and the second PFC circuit corresponds to a reference voltage when the connection of the load is not detected, wherein the reference voltage is less than an AC rectified voltage of the electronic device.

[0008] According to one embodiment of the present disclosure for achieving the above-described object, a computer-readable recording medium including a program for executing a control method of an electronic device including a first PFC (power factor correction) circuit and a second PFC circuit, wherein the control method of the electronic device includes the steps of detecting whether a load is connected and, based on the connection of the load, applying a first signal for controlling on-off of the first PFC circuit to a first switch in the first PFC circuit to control the first PFC circuit and applying a second signal for controlling on-off of the second PFC circuit to a second switch in the second PFC circuit to control the second PFC circuit, wherein the controlling step includes the step of controlling the first PFC circuit and the second PFC circuit so that an output voltage of each of the first PFC circuit and the second PFC circuit corresponds to a reference voltage when the connection of the load is not detected, wherein the reference voltage is less than an AC rectified voltage of the electronic device.

[0009] Figure 1 is a circuit diagram for explaining the burst mode of a PFC circuit according to the prior art.

[0010] FIG. 2 is a block diagram illustrating the configuration of an electronic device according to an embodiment of the present disclosure.

[0011] FIG. 3 is a circuit diagram illustrating an electronic device including a first PFC circuit and a second PFC circuit according to one embodiment of the present disclosure.

[0012] Fig. 4 is a graph for explaining the burst mode and output voltage of a PFC circuit according to the prior art.

[0013] FIG. 5 is a graph for explaining the off and output voltage of a PFC circuit according to one embodiment of the present disclosure.

[0014] FIG. 6 is a graph for explaining changes in a switching signal when a PFC circuit is turned off according to an embodiment of the present disclosure.

[0015] FIG. 7 is a graph for explaining a control circuit that applies a signal to either a first PFC circuit or a second PFC circuit according to one embodiment of the present disclosure.

[0016] FIG. 8 is a diagram illustrating an electronic device including a plurality of PFC circuits according to one embodiment of the present disclosure.

[0017] FIG. 9 is a flowchart for explaining a control method of an electronic device according to an embodiment of the present disclosure.

[0018] The terms used in this specification will be briefly explained, and the present disclosure will be described in detail.

[0019] The terms used in the embodiments of this disclosure have been selected from widely used, current terms, taking into account the functions of this disclosure. However, these terms may vary depending on the intentions of those skilled in the art, precedents, the emergence of new technologies, etc. Furthermore, in certain cases, terms may be arbitrarily selected by the applicant, and in such cases, their meanings will be described in detail in the description of the relevant disclosure. Therefore, the terms used in this disclosure should not be defined simply as names of terms, but rather based on the meanings of the terms and the overall content of this disclosure.

[0020] The embodiments of the present disclosure may be modified and have various embodiments. Specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the scope of the present disclosure to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the scope of the disclosed concepts and techniques. In describing the embodiments, detailed descriptions of related known technologies will be omitted if they are deemed to obscure the main point.

[0021] Terms such as "first" and "second" may be used to describe various components, but the components should not be limited by these terms. These terms are used solely to distinguish one component from another.

[0022] Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "comprise" or "consist of" are intended to indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but should be understood not to preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0023] In the present disclosure, a "module" or "part" performs at least one function or operation and may be implemented as hardware or software, or as a combination of hardware and software. Furthermore, multiple "modules" or multiple "parts" may be integrated into at least one module and implemented as at least one processor (not shown), excluding any "modules" or "parts" that need to be implemented as specific hardware.

[0024] Below, with reference to the attached drawings, embodiments of the present disclosure are described in detail so that those skilled in the art can easily implement the present disclosure. However, the present disclosure may be implemented in various different forms and is not limited to the embodiments described herein. In addition, in the drawings, parts irrelevant to the description are omitted for clarity of description of the present disclosure, and similar parts are designated with similar reference numerals throughout the specification.

[0025] Figure 1 is a circuit diagram for explaining the burst mode of a PFC circuit according to the prior art.

[0026] Referring to FIG. 1, various types of electronic devices (e.g., display devices, etc.) need to output large amounts of power as they become larger. For example, an electronic device (100) according to an example of the present disclosure may include a plurality of PFC circuits for driving the electronic device (100) or for supplying power to a load (e.g., a peripheral device) connected to the electronic device (100).

[0027] For example, when an electronic device (100) is implemented as a switched mode power supply (SMPS), the electronic device (100) includes a plurality of components to supply power, and the plurality of components can be divided into AC / DC blocks, DC / DC blocks, etc.

[0028] As illustrated in FIG. 1, it has been difficult for a conventional electronic device to output a large amount of power while maintaining a thin thickness of the electronic device (100) and satisfying standards (or regulations) related to standby power. In particular, a conventional electronic device including a plurality of PFC circuits to output a large amount of power has a problem in that it fails to satisfy standards related to standby power due to a switching signal (or switching current) when the plurality of PFC circuits operate in a burst mode.

[0029] An electronic device (100) according to an example of the present disclosure can output a large amount of power while satisfying standards related to standby power by including multiple PFC circuits. Below, a configuration of an electronic device (100) that controls multiple PFC circuits according to various embodiments of the present disclosure will be described.

[0030] FIG. 2 is a block diagram illustrating the configuration of an electronic device according to an embodiment of the present disclosure.

[0031] An electronic device (100) according to various embodiments of the present disclosure may include a first power factor correction (PFC) circuit (110), a second PFC circuit (120), and a control circuit (130).

[0032] Here, the electronic device (100) can receive a video signal by performing wired / wireless communication with an external device such as a PC, a set-top box, etc., and can also receive a video signal using a tuner, etc. provided in-house, or can obtain a video signal using video data stored in storage provided in the electronic device (100). Subsequently, the electronic device (100) can provide the video signal to an external device (e.g., a display device).

[0033] Meanwhile, the power line of the electronic device (100) is connected to a power outlet that provides commercial power (e.g., 90 to 264 V), and the electronic device (100) can transmit the commercial power to an external device (or, load).

[0034] An electronic device (100) according to one embodiment may be implemented as various types of devices that supply power to an external device.

[0035] The external device can be implemented as a display device and display video data. Here, the display device can be implemented as a TV, but is not limited thereto, and is applicable to any device with a display function, such as a video wall, a large format display (LFD), a digital signage, a digital information display (DID), a projector display, etc. In addition, the display device can be implemented as various types of displays, such as an LCD (liquid crystal display), an OLED (organic light-emitting diode), an LCoS (Liquid Crystal on Silicon), a DLP (Digital Light Processing), a QD (quantum dot) display panel, a QLED (quantum dot light-emitting diodes), a μLED (Micro light-emitting diodes), a Mini LED, etc. In addition, the display device can display a video signal received from the electronic device (100) and can be driven using power supplied from the electronic device (100).

[0036] In the above example, the electronic device (100) and the external device are implemented as separate entities. However, this is merely an example and is not limited thereto. The electronic device (100) and the external device may be implemented as a single entity. For example, the electronic device (100) may be implemented as a component (e.g., a power supply) of the external device.

[0037] An electronic device (100) (e.g., a power supply) according to one embodiment of the present disclosure is implemented as a switched mode power supply (SMPS) and may include a power factor correction circuit, i.e., a PFC circuit, to meet various regulations and increase in overall power consumption due to the enlargement of the electronic device (100).

[0038] According to one embodiment of the present disclosure, an electronic device (100) is a hardware that converts alternating current (AC) power into direct current (DC) power and stably supplies power to an internal load (or an external device) of the electronic device (100). The electronic device (100) includes a plurality of switches, and can control the on-off of each of the plurality of switches to provide stabilized power to the load.

[0039] Meanwhile, it goes without saying that the electronic device (100) according to one embodiment of the present disclosure may include a diode bridge (or bridge rectifier), an electromagnetic interference (EMI) filter, etc. For example, the diode bridge is a bridge circuit that connects four diodes, and may be a component that rectifies an AC input and changes it into a DC output.

[0040] According to one example of the present disclosure, the electronic device (100) may include an active bridge instead of a diode bridge.

[0041] An active bridge according to an example is one in which the four diodes that make up a conventional diode bridge are replaced with transistors (MOSFETs), and the efficiency of the converter (or power converter) can be increased because the active bridge has no rectifier diode forward conduction loss.

[0042] Additionally, the controller (e.g., an IC chip) that controls the active bridge has very low power consumption, and the power consumption of the active bridge may be less than that of the diode bridge in a mode where no load is connected to the electronic device (100) (e.g., standby mode).

[0043] The EMI filter section can remove electrical noise from commercial power supplies.

[0044] An electronic device (100) according to one embodiment may include a first PFC circuit (110) and a second PFC circuit (120). Here, each of the first PFC circuit (110) and the second PFC circuit (120) may be implemented as various types of converters, such as a buck, a boost, and a buck-boost converter.

[0045] Meanwhile, the electronic device (100) may operate in an intermittent switching mode to minimize power consumption and satisfy standards (or regulations) related to standby power. Here, the intermittent switching mode may be referred to as a burst mode, a standby mode, etc., but for convenience of explanation, it will be collectively referred to as a standby mode hereinafter.

[0046] First, in standby mode, the control circuit (130) of the electronic device (100) can operate the first PFC circuit (110) and the second PFC circuit (120) in standby mode when the magnitude of the current flowing in the first PFC circuit (110) and the second PFC circuit (120) is maintained below the threshold current.

[0047] Meanwhile, the electronic device (100) includes a plurality of PFC circuits (e.g., a first PFC circuit (110) and a second PFC circuit (120)) to output a large amount of power, and when the electronic device (100) operates each of the plurality of PFC circuits in standby mode, the standard related to standby power may not be satisfied due to intermittent switching current.

[0048] For example, in standby mode of the electronic device (100), the standby power of the electronic device (100) may exceed the reference power (e.g., 0.5 W) due to the switching signal applied to each of the plurality of PFC circuits.

[0049] A control circuit (130) according to an example of the present disclosure can control an electronic device (100) by changing the output voltage of each of the AC / DC blocks, i.e., a plurality of PFC circuits, to minimize loss due to a switching signal and to prevent the standby power of the electronic device (100) from exceeding a reference power.

[0050] Meanwhile, the control circuit (130) may be implemented as a digital signal control circuit (digital signal processor (DSP)) for processing a digital image signal, a microcontroller, or a T-CON (Timing controller). However, the present invention is not limited thereto, and may include one or more of a central processing unit (CPU), a microcontroller unit (MCU), a microprocessing unit (MPU), a controller, an application control circuit (AP), a communication control circuit (CP), or an ARM control circuit, or may be defined by the relevant terms. In addition, the control circuit (130) may be implemented as a system on chip (SoC) having a built-in processing algorithm, a large scale integration (LSI), or may be implemented in the form of a field programmable gate array (FPGA).

[0051] Additionally, the control circuit (130) may be implemented as an IC (Integrated Circuit) provided in each of the AC / DC block and the DC / DC block.

[0052] For example, the control circuit (130) may include a control circuit provided in the active bridge to control the active bridge, a control circuit provided in the first PFC circuit (110), a control circuit provided in the second PFC circuit (120), and a control circuit provided in a DC / DC block (e.g., an LLC converter).

[0053] Hereinafter, the configuration of an electronic device (100) that controls a plurality of PFC circuits according to various embodiments of the present disclosure will be described with reference to a circuit diagram.

[0054] FIG. 3 is a circuit diagram illustrating an electronic device including a first PFC circuit and a second PFC circuit according to one embodiment of the present disclosure.

[0055] Referring to FIG. 3, the electronic device (100) may include a first PFC circuit (110) and a second PFC circuit (120) connected in parallel with the first PFC circuit (110).

[0056] A control circuit (130) according to an example can detect whether a load is connected and apply a first signal for controlling on-off of a first PFC circuit (110) to a first switch in the first PFC circuit, and can apply a second signal for controlling on-off of a second PFC circuit (120) to a second switch in the second PFC circuit.

[0057] <Standby mode of the first PFC circuit (110) and the second PFC circuit (120)>

[0058] If the connection of the load is not detected, the control circuit (130) can control the first PFC circuit (110) and the second PFC circuit (120) so that the output voltage of each of the first PFC circuit (110) and the second PFC circuit (120) corresponds to the reference voltage.

[0059] A control circuit (130) according to an example of the present disclosure can detect the output voltages of the first PFC circuit (110) and the second PFC circuit (120).

[0060] Next, if the output voltage of each of the first PFC circuit (110) and the second PFC circuit (120) is less than a set value (hereinafter, a reference voltage), the control circuit (130) can apply a first signal (e.g., a gate signal) for on-off control of the first switch included in the first PFC circuit (110) and a second signal for on-off control of the second switch included in the second PFC circuit (120).

[0061] Here, the signal may include a signal supplied to the gate to cause current to flow through the switch. Meanwhile, in the present disclosure, "a configuration for turning on a switch" means changing the switch from a non-conductive state to a conducting state. In particular, it means supplying a signal to the gate to cause current to flow through the switch. On the other hand, "a configuration for turning off a switch" means changing the switch from a conducting state to a non-conductive state.

[0062] For example, when the control circuit (130) applies a signal to the first switch, the current flowing in the inductor included in the first PFC circuit (110) increases, and the output voltage of the first PFC circuit (110) may also increase. In addition, when the control circuit (130) applies a signal to the second switch, the output voltage of the second PFC circuit (120) may also increase.

[0063] For example, the control circuit (130) may not apply a signal to the first switch when the output voltage of the first PFC circuit (110) increases to correspond to (or reaches) the reference voltage. In addition, the control circuit (130) may not apply a signal to the second switch when the output voltage of the second PFC circuit (120) increases to correspond to the reference voltage.

[0064] In one example, the control circuit (130) according to one example of the present disclosure can change the reference voltage to less than the AC rectified voltage if the connection of the load is not detected.

[0065] According to an example of the present disclosure, when no load is connected to the electronic device (100), the output voltage of the first PFC circuit (110) corresponds to the AC rectified voltage, so the control circuit (130) may not apply a signal (e.g., a first signal for turning on the first switch) to cause the output voltage of the first PFC circuit (110) to reach the AC rectified voltage.

[0066] According to an example of the present disclosure, since the output voltage of the first PFC circuit (110) is maintained at the AC rectified voltage when no load is connected to the electronic device (100), the output voltage of the first PFC circuit (110) does not fall below the reference voltage (i.e., the output voltage of the first PFC circuit (110) is maintained above the reference voltage), and the control circuit (130) may not apply a signal to the first switch of the first PFC circuit (110).

[0067] Therefore, a switching signal for intermittently turning on the first switch provided in the first PFC circuit (110) may not be generated.

[0068] The above-described example can be equally applied to the second PFC circuit (120). For example, since the output voltage of the second PFC circuit (120) is maintained as an AC rectified voltage when no load is connected to the electronic device (100), the output voltage of the second PFC circuit (120) does not fall below the reference voltage, and the control circuit (130) may not apply a signal to the second switch of the second PFC circuit (110).

[0069] Therefore, a switching signal for intermittently turning on the second switch provided in the second PFC circuit (110) may not be generated.

[0070] A control circuit (130) according to an example of the present disclosure can control an electronic device (100) to change a reference voltage to be less than an AC rectified voltage when no load is connected, and to maintain the output voltage of each of the AC / DC blocks, i.e., a plurality of PFC circuits, at the AC rectified voltage, thereby minimizing loss due to a switching signal and ensuring that the standby power of the electronic device (100) does not exceed a reference power (e.g., 0.5 W).

[0071] Meanwhile, the standby mode of each of the first PFC circuit (110) and the second PFC circuit (120) may include a state in which no load connection to the electronic device (100) is detected, a state in which the magnitude of the current flowing through each of the first PFC circuit (110) and the second PFC circuit (120) is maintained below a threshold current, etc.

[0072] Fig. 4 is a graph for explaining the burst mode and output voltage of a PFC circuit according to the prior art.

[0073] Referring to FIG. 4, a graph is shown showing changes in the output voltages of the first PFC circuit and the second PFC circuit after AC power is applied to an electronic device according to the prior art.

[0074] For example, conventional electronic devices can operate the PFC circuit in standby mode when the magnitude of the current flowing through the PFC circuit remains below a threshold current.

[0075] A control circuit equipped in a conventional electronic device can generate a switching signal to intermittently turn on a switch equipped in the PFC circuit when the output voltage of the PFC circuit decreases and falls below the reference voltage and reaches a threshold voltage in the burst mode of the PFC circuit, i.e., standby mode.

[0076] When a switching signal is applied to the switch and the PFC circuit is turned on, the output voltage of the PFC circuit increases to correspond to the reference voltage.

[0077] If the output voltage of the PFC circuit corresponds to the reference voltage, the control circuit may not apply a switching signal to the PFC circuit.

[0078] However, when conventional electronic devices are equipped with multiple PFC circuits to output a large amount of power, and an intermittent switching signal is applied to each of the multiple PFC circuits, there is a problem in that the standby power exceeds the reference power (e.g., 0.5 W).

[0079] FIG. 5 is a graph for explaining the off and output voltage of a PFC circuit according to one embodiment of the present disclosure.

[0080] Referring to FIG. 5, after AC power is applied to the electronic device (100), when the connection of a load is detected (High Load in FIG. 5), each of the first PFC circuit (110) and the second PFC circuit (120) performs a boost operation, and the output voltage of each of the first PFC circuit (110) and the second PFC circuit (120) can reach a steady state in which the output voltage is maintained constant.

[0081] For example, when the connection of a load is detected, the control circuit (130) can apply a first signal to the first switch to turn on the first switch, and apply a second signal to the second switch to turn on the second switch, thereby operating each of the first PFC circuit (110) and the second PFC circuit (120) in boost mode.

[0082] Meanwhile, if the connection of the load is not detected (Low Load in FIG. 5), the control circuit (130) can control the first PFC circuit (110) and the second PFC circuit (120) so that the output voltages of each of the first PFC circuit (110) and the second PFC circuit (120) correspond to the reference voltage. Here, the reference voltage may be less than the AC rectified voltage.

[0083] For example, since the output voltage of each of the first PFC circuit (110) and the second PFC circuit (120) is maintained above the reference voltage, the control circuit (130) does not apply an intermittent switching signal to each of the first PFC circuit (110) and the second PFC circuit (120), and the standby power of the electronic device (100) may not exceed the reference power (e.g., 0.5 W).

[0084] According to one example of the present disclosure, an electronic device (100) includes a DC / DC block (e.g., an LLC converter), and the LLC converter can be connected to each of a first PFC circuit (110) and a second PFC circuit (120).

[0085] According to one example of the present disclosure, the control circuit (130) does not apply a switching signal to each of the first PFC circuit (110) and the second PFC circuit (120) while the connection of the load is not detected (i.e., controls each of the first PFC circuit (110) and the second PFC circuit (120) to be off), and the LLC converter can be operated in an intermittent switching mode (or burst mode).

[0086] According to an example of the present disclosure, the control circuit (130) can detect whether a load is connected based on a high signal or a low signal of a load detection pin (Pin) (Load Det). Here, the control circuit (130) may be a control circuit (e.g., an IC chip) provided in the LLC converter.

[0087] For example, the load detection pin receives a detection (Det) signal from the active bridge included in the first PFC circuit (110) and the second PFC circuit (120), and if the detection signal is a High signal, it can detect that the load is connected, and if the detection signal is a Low signal, it can detect that the load is not connected.

[0088] However, this is just an example and is not limited to this.

[0089] For example, the electronic device (100) of the present disclosure may include an output section that is capable of connecting a load and includes a synchronous rectifier, and the control circuit (130) may detect whether the load is connected based on whether the synchronous rectifier provided in the output section is operating. In one example, the output section may be called a secondary circuit, and for the convenience of explanation, it will be collectively referred to as the output section hereinafter. In one example, the control circuit (130) may include a control circuit (e.g., an IC chip) provided in the secondary circuit.

[0090] FIG. 6 is a graph for explaining changes in switching current when a PFC circuit is turned off according to an embodiment of the present disclosure.

[0091] Referring to the left graph of Fig. 6, since a conventional electronic device has multiple PFC circuits operating in burst mode, an intermittent switching signal is applied to each of the multiple PFC circuits, which causes a problem in that the standby power of the electronic device in burst mode exceeds the reference power.

[0092] However, referring to the right graph of FIG. 6, when a load is not connected, the electronic device (100) can prevent an increase in standby power due to an intermittent switching signal by turning off each of the plurality of PFC circuits.

[0093] For example, if the control circuit (130) sets the reference voltage to be less than the AC rectified voltage, the output voltages of the first PFC circuit (110) and the second PFC circuit (120) are maintained above the AC rectified voltage without turning on the first switch provided in the first PFC circuit (110) and the second switch provided in the second PFC circuit (120), respectively, so that the first PFC circuit (110) and the second PFC circuit (120) can be automatically turned off.

[0094] FIG. 7 is a graph for explaining a control circuit that applies a signal to either a first PFC circuit or a second PFC circuit according to one embodiment of the present disclosure.

[0095] Referring to FIG. 7, if the connection of the load is not detected, the control circuit (130) can control the first PFC circuit (110) so that the output voltage of the first PFC circuit (110) corresponds to the first reference voltage, and can control the second PFC circuit (120) so that the output voltage of the second PFC circuit (120) corresponds to the second reference voltage.

[0096] For example, when no load is connected to the electronic device (100), the control circuit (130) can apply an intermittent switching signal to the first PFC circuit (110) to operate the first PFC circuit (110) in a burst mode and automatically turn off the second PFC circuit (120).

[0097] For example, when a load is not connected, the electronic device (100) can control the first PFC circuit (110) so that the output voltage of the first PFC circuit (110) corresponds to a first reference voltage. Here, the first reference voltage can be an AC rectified voltage or higher but an output voltage of the first PFC circuit (110) or lower in boost mode (i.e., AC rectified voltage - output voltage of the first PFC circuit (110) in boost mode).

[0098] For example, the control circuit (130) can generate a switching signal to intermittently turn on the first switch of the first PFC circuit (110) when the output voltage of the first PFC circuit (110) reaches a threshold voltage. The control circuit (130) can control the first PFC circuit (110) by applying the switching signal to the first switch to intermittently turn on the first PFC circuit (110) so that the output voltage of the first PFC circuit (110) corresponds to the reference voltage.

[0099] Meanwhile, when a load is not connected, the electronic device (100) can control the second PFC circuit (120) so that the output voltage of the second PFC circuit (110) corresponds to the second reference voltage. Here, the second reference voltage may be lower than the AC rectified voltage.

[0100] For example, the control circuit (130) may not generate a switching signal to intermittently turn on the second switch of the second PFC circuit (120) because the output voltage of the second PFC circuit (120) is maintained above the reference voltage, i.e., the AC rectified voltage.

[0101] For example, the control circuit (130) may not generate a switching signal corresponding to each of the plurality of PFC circuits, but may generate a switching signal corresponding to at least one PFC circuit among the plurality of PFC circuits. For example, the control circuit (130) may generate a switching signal corresponding to the first PFC circuit (110), and may not generate a switching signal corresponding to the second PFC circuit (120).

[0102] For example, by generating a switching signal corresponding to at least one PFC circuit among a plurality of PFC circuits and not generating a switching signal corresponding to the remaining PFC circuits, in a standby mode (i.e., a state in which no load is connected to the electronic device (100), the standby power of the electronic device (100) due to the switching signal applied to the at least one PFC circuit may not exceed a reference power (e.g., 0.5 W).

[0103] In the above example, for convenience of explanation, an electronic device (100) including a first PFC circuit (110) and a second PFC circuit (120) is assumed and described, but it is obvious that the electronic device (100) may include a plurality of PFC circuits.

[0104] FIG. 8 is a diagram illustrating an electronic device including a plurality of PFC circuits according to one embodiment of the present disclosure.

[0105] Referring to FIG. 8, the electronic device (100) may include first to fourth PFC circuits connected in parallel with each other.

[0106] In one example, the electronic device (100) may include a plurality of PFC circuits to output a large amount of power, and the plurality of FPC circuits may be connected in parallel with each other.

[0107] As an example, when a load is connected to the electronic device (100) and the electronic device (100) outputs 600 W of power, each of the first to fourth PFC circuits can output 150 W.

[0108] For example, when no load is connected to the electronic device (100), the control circuit (130) may operate at least one of the first to fourth PFC circuits (e.g., the first PFC circuit (110)) in a burst mode, thereby applying an intermittent switching signal to the first switch provided in the first PFC circuit (110).

[0109] For example, the control circuit (130) may control the remaining PFC circuits (e.g., the second to fourth PFC circuits) so that their output voltages correspond to a reference voltage lower than the AC rectified voltage. The control circuit (130) may not apply intermittent switching signals to the remaining PFC circuits. Accordingly, the remaining PFC circuits may be automatically turned off.

[0110] For example, the first to fourth PFC circuits are connected in parallel with each other, so that while the connection of the load is not detected, the output voltage of the first PFC circuit (110) can be the same as the output voltage of the remaining PFC circuits (i.e., the second to fourth PFC circuits).

[0111] FIG. 9 is a flowchart for explaining a control method of an electronic device according to an embodiment of the present disclosure.

[0112] A control method of an electronic device including a first PFC (power factor correction) circuit and a second PFC circuit according to an example of the present disclosure detects whether a load is connected (S910).

[0113] The control method controls the first PFC circuit by applying a first signal for controlling on-off of the first PFC circuit to a first switch in the first PFC circuit based on whether a load is connected, and controls the second PFC circuit by applying a second signal for controlling on-off of the second PFC circuit to a second switch in the second PFC circuit (S920).

[0114] In an embodiment, step S920 of controlling includes a step of controlling the first PFC circuit and the second PFC circuit so that the output voltages of each of the first PFC circuit and the second PFC circuit correspond to a reference voltage if the connection of the load is not detected. The reference voltage may be less than the AC rectified voltage of the electronic device.

[0115] An electronic device according to an example of the present disclosure further includes an LLC converter connected to a first PFC circuit and a second PFC circuit, and the controlling step S920 may include a step of controlling the first PFC circuit and the second PFC circuit to be turned off and operating the LLC converter in a burst mode while the connection of a load is not detected.

[0116] An electronic device according to an example of the present disclosure further includes an LLC converter and a bridge connected to a first PFC circuit and a second PFC circuit, and the detecting step S910 may include a step of detecting whether a load is connected based on a detection (DET) signal received by the LLC converter from the bridge.

[0117] According to one example of the present disclosure, a bridge includes an active bridge including a plurality of transistors (FETs) and an IC for controlling each of the plurality of transistors, and the step S910 of detecting may include a step of receiving a detection signal from the IC through an LLC converter, and the step S920 of controlling may include a step of controlling the first PFC circuit and the second PFC circuit so that the output voltages of each of the first PFC circuit and the second PFC circuit correspond to a reference voltage if the connection of the load is not detected according to the detection signal.

[0118] In one example of the present disclosure, the controlling step S920 includes the step of applying a first signal for turning off the first switch to the first switch and applying a second signal for turning off the second switch to the second switch when the output voltage of each of the first PFC circuit and the second PFC circuit is equal to or higher than the reference voltage, wherein in the off state of each of the first PFC circuit and the second PFC circuit, the output voltage of each of the first PFC circuit and the second PFC circuit may be equal to or higher than the AC rectified voltage.

[0119] An electronic device according to an example of the present disclosure further includes an output section capable of connecting a load and including a synchronous rectifier, and the detecting step S910 may include a step of detecting whether the load is connected based on whether the synchronous rectifier is operating.

[0120] In one example of the present disclosure, the controlling step S920 may include a step of, when a connection of a load is detected, applying a first signal for turning on the first switch to the first switch and applying a second signal for turning on the second switch to the second switch, thereby operating each of the first PFC circuit and the second PFC circuit in a boost mode.

[0121] The controlling step S920 according to an example of the present disclosure includes a step of controlling the first PFC circuit so that the output voltage of the first PFC circuit corresponds to the first reference voltage, and controlling the second PFC circuit so that the output voltage of the second PFC circuit corresponds to the second reference voltage, if the connection of the load is not detected, wherein the first reference voltage may be equal to or greater than the AC rectified voltage, and the second reference voltage may be equal to or less than the AC rectified voltage.

[0122] The controlling step S920 according to an example of the present disclosure may include a step of operating the first PFC circuit in a burst mode and controlling the second PFC circuit to be turned off while the connection of the load is not detected.

[0123] An electronic device according to an example of the present disclosure further includes a third PFC circuit connected in parallel to each of the first PFC circuit and the second PFC circuit, and the controlling step S920 includes a step of controlling the third PFC circuit so that an output voltage of the third PFC circuit corresponds to a third reference voltage when a connection of a load is not detected, wherein the third reference voltage may be less than an AC rectified voltage.

[0124] However, it goes without saying that the various embodiments of the present disclosure can be applied not only to electronic devices, but also to all types of electronic devices equipped with SMPS.

[0125] Meanwhile, the various embodiments described above may be implemented in a computer-readable recording medium or similar device using software, hardware, or a combination thereof. In some cases, the embodiments described herein may be implemented by the processor itself. In a software implementation, embodiments, such as the procedures and functions described herein, may be implemented as separate software modules. Each of the software modules may perform one or more functions and operations described herein.

[0126] Meanwhile, computer instructions for performing processing operations of the electronic device (100) according to the various embodiments of the present disclosure described above may be stored in a non-transitory computer-readable medium. When the computer instructions stored in the non-transitory computer-readable medium are executed by a processor of a specific device, they cause the specific device to perform processing operations in the electronic device (100) according to the various embodiments described above.

[0127] A non-transitory computer-readable medium refers to a medium that permanently stores data and can be read by a device, rather than a medium that stores data for a short period of time, such as a register, cache, or memory. Specific examples of non-transitory computer-readable media include CDs, DVDs, hard disks, Blu-ray discs, USBs, memory cards, and ROMs.

[0128] Although the preferred embodiments of the present disclosure have been illustrated and described above, the present disclosure is not limited to the specific embodiments described above, and various modifications may be made by a person having ordinary skill in the art to which the present disclosure pertains without departing from the gist of the present disclosure as claimed in the claims, and such modifications should not be understood individually from the technical idea or prospect of the present disclosure.

Claims

1. In electronic devices, 1st PFC circuit; a second PFC circuit connected in parallel with the first PFC circuit; and A control circuit for detecting whether a load is connected and applying a first signal for controlling on-off of the first PFC circuit to a first switch in the first PFC circuit to control the first PFC circuit, and for applying a second signal for controlling on-off of the second PFC circuit to a second switch in the second PFC circuit to control the second PFC circuit; comprising: The above control circuit, If the connection of the above load is not detected, the first PFC circuit and the second PFC circuit are controlled so that the output voltage of each of the first PFC circuit and the second PFC circuit corresponds to the reference voltage. The above reference voltage is, An electronic device having an AC rectified voltage less than the rated voltage of said electronic device.

2. In paragraph 1, Further comprising an LLC converter connected to the first PFC circuit and the second PFC circuit; The above control circuit, An electronic device that controls the first PFC circuit and the second PFC circuit to be turned off and operates the LLC converter in burst mode while the connection of the load is not detected.

3. In paragraph 1, An LLC converter connected to the first PFC circuit and the second PFC circuit; and Further comprising a bridge connected in parallel to each of the first PFC circuit and the second PFC circuit; The above control circuit, An electronic device that detects whether the load is connected based on a detection (DET) signal received from the bridge by the LLC converter.

4. In paragraph 3, The above bridge, An active bridge comprising multiple transistors (FETs); and An IC for controlling each of the above-mentioned plurality of transistors; The above LLC converter receives the detection signal from the IC, The above control circuit, An electronic device that controls the first PFC circuit and the second PFC circuit so that the output voltages of each of the first PFC circuit and the second PFC circuit correspond to the reference voltage when the connection of the load is not detected according to the detection signal.

5. In paragraph 4, The above control circuit, When the output voltage of each of the first PFC circuit and the second PFC circuit is higher than the reference voltage, the first signal for turning off the first switch is applied to the first switch, and the second signal for turning off the second switch is applied to the second switch. An electronic device, wherein, in the off state of each of the first PFC circuit and the second PFC circuit, the output voltage of each of the first PFC circuit and the second PFC circuit is equal to or higher than the AC rectified voltage.

6. In paragraph 1, The above load can be connected, and further includes an output section including a synchronous rectifier; The above control circuit, An electronic device that detects whether the load is connected or not based on whether the synchronous rectifier is operating or not.

7. In paragraph 1, The above control circuit, An electronic device, wherein when the connection of the load is detected, the first signal for turning on the first switch is applied to the first switch, and the second signal for turning on the second switch is applied to the second switch, thereby operating each of the first PFC circuit and the second PFC circuit in boost mode.

8. In paragraph 1, The above control circuit, If the connection of the above load is not detected, the first PFC circuit is controlled so that the output voltage of the first PFC circuit corresponds to the first reference voltage. Controlling the second PFC circuit so that the output voltage of the second PFC circuit corresponds to the second reference voltage, The above first reference voltage is greater than or equal to the AC rectified voltage, An electronic device wherein the second reference voltage is less than the AC rectified voltage.

9. In paragraph 8, The above control circuit, An electronic device that operates the first PFC circuit in burst mode and controls the second PFC circuit to be off while the connection of the load is not detected.

10. In paragraph 8, Further comprising a third PFC circuit connected in parallel to each of the first PFC circuit and the second PFC circuit; The above control circuit, If the connection of the above load is not detected, the third PFC circuit is controlled so that the output voltage of the third PFC circuit corresponds to the third reference voltage. An electronic device wherein the third reference voltage is less than the AC rectified voltage.

11. A method for controlling an electronic device including a first PFC (power factor correction) circuit and a second PFC circuit, A step for detecting whether the load is connected; and A step of controlling the first PFC circuit by applying a first signal for controlling on-off of the first PFC circuit to a first switch in the first PFC circuit based on whether the load is connected, and controlling the second PFC circuit by applying a second signal for controlling on-off of the second PFC circuit to a second switch in the second PFC circuit; The above controlling step is, If the connection of the load is not detected, a step of controlling the first PFC circuit and the second PFC circuit so that the output voltage of each of the first PFC circuit and the second PFC circuit corresponds to the reference voltage; The above reference voltage is, A control method wherein the AC rectified voltage of the electronic device is less than the rated voltage.

12. In paragraph 11, The electronic device further includes an LLC converter connected to the first PFC circuit and the second PFC circuit, The above controlling step is, A control method, comprising: a step of controlling the first PFC circuit and the second PFC circuit to be turned off and operating the LLC converter in burst mode while the connection of the load is not detected.

13. In paragraph 11, The electronic device further includes an LLC converter and a bridge connected to the first PFC circuit and the second PFC circuit, The above detection step is, A control method, comprising: a step of detecting whether the load is connected based on a detection (DET) signal received from the bridge by the LLC converter.

14. In paragraph 13, The above bridge, An active bridge comprising a plurality of transistors (FETs) and an IC controlling each of the plurality of transistors, The above detection step is, A step of receiving the detection signal from the IC through the LLC converter; The above controlling step is, A control method, comprising: a step of controlling the first PFC circuit and the second PFC circuit so that the output voltages of each of the first PFC circuit and the second PFC circuit correspond to the reference voltage if the connection of the load is not detected according to the detection signal; 15. In paragraph 14, The above controlling step is, A step of applying the first signal for turning off the first switch to the first switch and applying the second signal for turning off the second switch to the second switch when the output voltage of each of the first PFC circuit and the second PFC circuit is higher than the reference voltage; includes; A control method, wherein, in the off state of each of the first PFC circuit and the second PFC circuit, the output voltage of each of the first PFC circuit and the second PFC circuit is equal to or higher than the AC rectified voltage.

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