WO2022244998A1

WO2022244998A1 - Display device and control method therefor

Info

Publication number: WO2022244998A1
Application number: PCT/KR2022/005733
Authority: WO
Inventors: 정성범; 주성용; 강정일
Original assignee: 삼성전자주식회사
Priority date: 2021-05-18
Filing date: 2022-04-21
Publication date: 2022-11-24
Also published as: KR20220156256A

Abstract

A display device is disclosed. The present display device comprises: a first voltage-dividing circuit which includes a power supply circuit and a plurality of capacitors, and which divides voltage supplied from the power supply circuit to output the divided voltage; and a second voltage-dividing circuit which includes a plurality of capacitors, and which divides the voltage supplied from the power supply circuit to output the divided voltage, wherein an output end of the first voltage-dividing circuit and an output end of the second voltage-dividing circuit are connected in series to provide an output voltage based on a first output voltage of the first voltage-dividing circuit and a second output voltage of the second voltage-dividing circuit.

Description

Display device and its control method

The present disclosure relates to a display device and a control method thereof, and more particularly, to a display device converting power and supplying power to each component and a control method thereof.

With the introduction of self-luminous displays such as OLED TVs, DC converters for low-voltage, high-current loads are being developed.

As shown in FIG. 1A, the DC-DC converter circuit using the magnetic material L1 has a problem in that the size and heat generation of the inductor greatly increase when the circuit is configured with high capacity and large current. In addition, there are constraints on the size of parts in order to manufacture a DC-DC converter circuit in an ultra-small and ultra-thin form, but in the case of a magnetic material, there are no ultra-thin parts, so it is difficult to manufacture an ultra-thin converter of about 6 mm or less.

Accordingly, as shown in FIG. 1B , a voltage dividing converter using a capacitor (C1) rather than an inductor may be used. A voltage divider using a capacitor is a converter that can step up or step down a voltage using a capacitor without a magnetic substance. Since a magnetic substance is not used, a compact and ultra-thin design is possible, and it has high efficiency and no heat generation.

The capacitor used in the voltage divider using a capacitor is an MLCC (Multi Layer Ceramic Capacitor) considering the capacity and size, but there is a problem that there are almost no high-capacity MLCC with a high withstand voltage of 100V or more. That is, there is a problem in that the number of parallel connections of MLCCs greatly increases for high-capacity application. In addition, due to DC bias characteristics in which capacitance decreases as the voltage applied to the MLCC increases, there is a problem of selecting an MLCC having a withstand voltage margin twice or more higher than the required withstand voltage. In addition, there are PL (Product Liability) accidents such as ignition and heat due to defective MLCC cracks, and the higher the voltage, the greater the risk of PL accidents.

Due to the above problems, many MLCCs of 50V or less have been developed, but high-capacity MLCCs of 50V or more have hardly been developed.

In addition, voltage divider converters using capacitors are designed with step-up and step-down ratios that are multiples of 2, such as 2 and 4 (1:2, 2:1, 1:4, and 4:1), and the step-up and step-down ratios are fixed, so the output voltage can be varied. There is an unavoidable problem.

Accordingly, it is necessary to develop a circuit in which the above problem is solved.

SUMMARY OF THE INVENTION The present disclosure has been made in accordance with the above-described needs, and an object of the present disclosure is to provide a display device capable of performing a high-capacity DC-DC conversion operation using a conventional capacitor and a control method thereof.

According to an embodiment of the present disclosure for achieving the above object, a display device includes a power supply circuit and a plurality of capacitors, and a first voltage divider circuit for dividing and outputting a voltage supplied from the power supply circuit, and a plurality of voltage dividers. and a second voltage divider circuit that divides and outputs a voltage supplied from the power supply circuit, wherein an output terminal of the first voltage divider circuit and an output terminal of the second voltage divider circuit are connected in series to the first voltage divider circuit. An output voltage based on the first output voltage of the voltage divider circuit and the second output voltage of the second voltage divider circuit may be provided.

Also, one end of the output terminals of the first voltage divider circuit may be connected to one of the output terminals of the second voltage divider circuit, and the other end of the output terminals of the second voltage divider circuit may be connected to ground.

And, based on a first resistor having one end connected to the input terminal of the second voltage divider circuit, a second resistor having one end connected to the other end of the first resistor and the other end connected to the earth ground, and a voltage at one end of the second resistor. It may further include a first feedback circuit for controlling the output of the power supply circuit.

The method further includes a third resistor having one end connected to the other end of the first resistor and one end of the second resistor, and a first transistor connected to the other end of the third resistor, wherein the first transistor is PWM input through a gate. (Pulse Width Modulation) The voltage of one end of the second resistor may be changed based on the duty of the control signal.

Also, the other end of the output end of the first voltage divider circuit may be connected to a ground different from the earth ground.

In addition, a fourth resistor having one end connected to the input terminal of the first voltage divider circuit, a fifth resistor having one end connected to the other end of the fourth resistor and the other end connected to a ground different from the earth ground, and one end of the fifth resistor It may further include a second feedback circuit for controlling the output of the power supply circuit based on the voltage.

And, a sixth resistor having one end connected to the other end of the fourth resistor and one end of the fifth resistor and a second transistor connected to the other end of the sixth resistor, wherein the second transistor is PWM input through a gate. A voltage of one end of the fifth resistor may be changed based on the duty of the control signal.

The first voltage divider circuit is controlled based on a first PWM signal and a second PWM signal obtained by inverting the first PWM signal, and the second voltage divider circuit has a predetermined phase difference with the first PWM signal. 3 PWM signals and the third PWM signal may be controlled based on the inverted fourth PWM signal.

The period T of the first PWM signal may be the same as the period of the third PWM signal, and the predetermined phase difference may be greater than or equal to -T/4 and less than or equal to T/4.

In addition, the power supply circuit includes a first sub power supply circuit and a second sub power supply circuit, wherein the first voltage divider circuit divides and outputs a voltage supplied from the first sub power supply circuit, and The voltage divider circuit may divide and output the voltage supplied from the second sub power supply circuit.

Meanwhile, according to an embodiment of the present disclosure, a control method of a display device includes supplying voltage by a power supply circuit, dividing the voltage by a first voltage dividing circuit, and connecting an output terminal and an output terminal of the first voltage dividing circuit in series. and dividing the voltage by a second voltage divider circuit connected thereto and providing an output voltage based on the first output voltage of the first voltage divider circuit and the second output voltage of the second voltage divider circuit.

The display device further includes a first resistor having one end connected to the input terminal of the second voltage divider circuit, a second resistor having one end connected to the other end of the first resistor and the other end connected to the ground, and a first feedback circuit. In the providing step, the first feedback circuit may control an output of the power supply circuit based on a voltage of one end of the second resistor.

The display device further includes a third resistor having one end connected to the other end of the first resistor and one end of the second resistor, and a first transistor connected to the other end of the third resistor, and controlling the output comprises A voltage of one end of the second resistor may be changed based on a duty of a pulse width modulation (PWM) control signal input through a gate of the first transistor.

In addition, the display device includes a fourth resistor having one end connected to the input terminal of the first voltage divider circuit, a fifth resistor having one end connected to the other end of the fourth resistor and the other end connected to a ground different from the earth ground, and a second feedback A circuit may be further included, and in the providing, the second feedback circuit may control an output of the power supply circuit based on a voltage of one end of the fifth resistor.

The display device further includes a sixth resistor having one end connected to the other end of the fourth resistor and one end of the fifth resistor, and a second transistor connected to the other end of the sixth resistor, and controlling the output comprises A voltage of one end of the fifth resistor may be changed based on a duty cycle of a PWM control signal input through a gate of the second transistor.

In addition, the step of dividing the voltage may include controlling the first voltage dividing circuit based on a first PWM signal and a second PWM signal obtained by inverting the first PWM signal, and a third voltage dividing circuit having a predetermined phase difference with the first PWM signal. The second voltage divider circuit may be controlled based on a fourth PWM signal obtained by inverting the PWM signal and the third PWM signal.

In the supplying step, the first sub power supply circuit and the second sub power supply circuit included in the power supply circuit supply voltage, and in the voltage dividing step, the first sub power supply circuit supplies the first sub power supply. The voltage supplied from the circuit may be divided and output, and the second voltage divider circuit may divide and output the voltage supplied from the second sub power supply circuit.

According to various embodiments of the present disclosure as described above, in a display device, a plurality of voltage-dividing converters are connected in a cascade, so that a high-capacity DC-DC converting operation is possible even when a relatively low-capacity MLCC is used.

In addition, the display device may reduce ripple by controlling the plurality of voltage dividing converters using a plurality of PWM signals having a phase difference.

1A and 1B are drawings for explaining the prior art.

2 is a block diagram illustrating a configuration of a display device according to an exemplary embodiment of the present disclosure.

3 is a diagram for specifically explaining the configuration of a display device according to an embodiment of the present disclosure.

4 is a diagram for specifically explaining the configuration of a display device according to another embodiment of the present disclosure.

5 is a diagram specifically illustrating a configuration of a display device according to another exemplary embodiment of the present disclosure.

6 is a diagram for explaining a control method for reducing ripple according to an embodiment of the present disclosure.

7 is a diagram for explaining a result of a control method for reducing ripple according to an embodiment of the present disclosure.

8 is a flowchart illustrating a method of controlling a display device according to an embodiment of the present disclosure.

Hereinafter, the present disclosure will be described in detail with reference to the accompanying drawings.

The terms used in the embodiments of the present disclosure have been selected from general terms that are currently widely used as much as possible while considering the functions in the present disclosure, but they may vary depending on the intention or precedent of a person skilled in the art, the emergence of new technologies, and the like. . In addition, in a specific case, there is also a term arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the description of the disclosure. Therefore, terms used in the present disclosure should be defined based on the meaning of the term and the general content of the present disclosure, not simply the name of the term.

In this specification, expressions such as “has,” “can have,” “includes,” or “can include” indicate the existence of a corresponding feature (eg, numerical value, function, operation, or component such as a part). , which does not preclude the existence of additional features.

The expression at least one of A and/or B should be understood to denote either "A" or "B" or "A and B".

Expressions such as "first," "second," "first," or "second," as used herein, may modify various components regardless of order and/or importance, and may refer to one component It is used only to distinguish it from other components and does not limit the corresponding components.

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

In this specification, the term user may refer to a person using an electronic device or a device (eg, an artificial intelligence electronic device) using an electronic device.

Hereinafter, various embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings.

2 is a block diagram showing the configuration of a display device 100 according to an embodiment of the present disclosure. As shown in FIG. 2 , the display device 100 includes a power supply circuit 110 , a first voltage divider circuit 120 and a second voltage divider circuit 130 .

The display device 100 may supply power to each component. For example, the display device 100 may convert AC power into DC power and supply it to the internal components of the display device 100 . Alternatively, the display device 100 may convert power into a plurality of DC power sources having a plurality of voltage levels, and supply the plurality of DC power sources to a plurality of components inside the display device 100, respectively.

However, it is not limited thereto, and the display device 100 may be implemented as a device that is detachable from an external device, and any device capable of supplying power may be used.

The power supply circuit 110 may generate power and supply the generated power to the first voltage divider circuit 120 and the second voltage divider circuit 130 .

For example, the power supply circuit (Isolated Converter, 110) may supply the output from the main winding and the output from the auxiliary winding to the first voltage divider circuit 120 and the second voltage divider circuit 130.

* The first voltage divider circuit (SC Converter, 120) includes a plurality of capacitors, and can divide and output the voltage supplied from the power supply circuit 110.

For example, the first voltage divider circuit 120 may not include an inductor and may be implemented as a capacitor. Also, the first voltage divider circuit 120 may receive a voltage supplied from one of the output by the main winding and the output by the auxiliary winding of the power supply circuit 110, divide the input voltage, and output the divided voltage.

The second voltage dividing circuit (SC converter) 130 includes a plurality of capacitors, and may divide and output voltage supplied from the power supply circuit 110 .

For example, the second voltage divider circuit 130 may be implemented with a capacitor without including an inductor. In addition, the second voltage divider circuit 130 may receive a voltage supplied from the other one of the output by the main winding and the output by the auxiliary winding of the power supply circuit 110, divide the input voltage, and output the divided voltage.

The output terminal of the first voltage divider circuit 120 and the output terminal of the second voltage divider circuit 130 are connected in series, and the display device 100 provides the first output voltage of the first voltage divider circuit 120 and the output terminal of the second voltage divider circuit 130. ) It is possible to provide an output voltage based on the second output voltage. For example, one end of the output terminals of the first voltage divider circuit 120 may be connected to one of the output terminals of the second voltage divider circuit 130, and the other end of the output terminals of the second voltage divider circuit 130 may be connected to ground.

That is, the first voltage divider circuit 120 and the second voltage divider circuit 130 may be connected in a cascade structure to share the load. Accordingly, the capacitance and size of the capacitors included in each of the first voltage divider circuit 120 and the second voltage divider circuit 130 can be reduced (reducing the withstand voltage of the MLCC), and the first voltage divider circuit 120 and the second voltage divider circuit (130) The size of each can be reduced. In addition, as the capacity of the capacitor decreases, problems such as ignition and heat generation can be solved.

According to an embodiment, the display device 100 includes a first resistor having one end connected to the input terminal of the second voltage divider circuit 130, a second resistor having one end connected to the other end of the first resistor and the other end connected to the earth ground, and A first feedback circuit for controlling the output of the power supply circuit 110 based on the voltage of one end of the second resistor may be further included.

In addition, the display device 100 further includes a third resistor having one end connected to the other end of the first resistor and one end of the second resistor, and a first transistor connected to the other end of the third resistor, wherein the first transistor is input through a gate. A voltage of one end of the second resistor may be changed based on a duty of a pulse width modulation (PWM) control signal. That is, the output voltage of the second voltage divider circuit 130 can be changed by changing the reference voltage of the first feedback circuit.

According to the operation of changing the output voltage, it is possible to compensate for the output voltage according to the sudden load change, and it is possible to solve the conventional problem of not being able to change the output voltage. In addition, it is possible to simplify control and secure reliability by controlling only the output voltage of the second voltage divider circuit 130 . The feedback operation and the operation of changing the output voltage will be described in more detail through drawings to be described later.

According to another embodiment, the other end of the output end of the first voltage divider circuit 120 may be connected to a ground different from the earth ground. Further, the display device 100 includes a fourth resistor having one end connected to the input terminal of the first voltage divider circuit 120, and a fifth resistor having one end connected to the other end of the fourth resistor and the other end connected to a ground different from the earth ground. and a second feedback circuit for controlling the output of the power supply circuit 110 based on the voltage of one end of the fifth resistor.

In addition, the display device 100 further includes a sixth resistor having one end connected to the other end of the fourth resistor and one end of the fifth resistor, and a second transistor connected to the other end of the sixth resistor, the second transistor being input through a gate. A voltage of one end of the fifth resistor may be changed based on the duty cycle of the PWM control signal. That is, the output voltage of the first voltage divider circuit 120 can be changed by changing the reference voltage of the second feedback circuit.

This embodiment is almost the same as the previous embodiment, but the difference is that the output voltage of the first voltage divider circuit 120 is changed. In particular, while the output voltage of the second voltage divider 130 is connected to ground, the display device 100 has a variable output voltage obtained by summing the output voltages of the first voltage divider 120 and the second voltage divider 130. In addition, the fixed output voltage of the second voltage divider circuit 130 may be additionally output.

Meanwhile, according to another embodiment, the power supply circuit 110 includes a first sub power supply circuit and a second sub power supply circuit, and the first voltage divider circuit 120 is supplied from the first sub power supply circuit. The voltage is divided and output, and the second voltage divider circuit 130 may divide and output the voltage supplied from the second sub power supply circuit. In this case, there is an advantage in that temperature sharing is possible through the first sub power supply circuit and the second sub power supply circuit.

Meanwhile, the first voltage divider circuit 120 is controlled based on the first PWM signal and the second PWM signal obtained by inverting the first PWM signal, and the second voltage divider circuit 130 calculates a phase difference between the first PWM signal and a preset phase. It can be controlled based on the third PWM signal having and the fourth PWM signal inverted by the third PWM signal. Here, the period T of the first PWM signal is equal to the period of the third PWM signal, and the predetermined phase difference may be greater than or equal to -T/4 and less than or equal to T/4. Through this operation, the ripple can be reduced.

As described above, in the display device 100, the first voltage divider circuit 120 and the second voltage divider circuit 130 are connected in a cascade, and even if the voltage divider circuit is configured using a relatively low capacitance capacitor, high-capacity DC-DC conversion is performed. action is possible

In FIG. 2 , for convenience of description, it is assumed that two voltage divider circuits, the first voltage divider 120 and the second voltage divider 130, are connected in a cascade, but the present invention is not limited thereto. For example, the display device 100 may include three or more cascade-connected voltage divider circuits.

Hereinafter, the operation of the display device 100 will be described in more detail with reference to FIGS. 3 to 7 . 3 to 7 describe individual embodiments for convenience of description. However, the individual embodiments of FIGS. 3 to 7 may be implemented in any combination.

3 is a diagram for specifically explaining the configuration of the display device 100 according to an embodiment of the present disclosure.

The power supply circuit 110 may supply two powers, Vin1 and Vin2, the first voltage divider circuit 120 may divide and output Vin2, and the second voltage divider 130 may divide and output Vin1.

One end of the output terminals of the first voltage divider circuit 120 may be connected to one of the output terminals of the second voltage divider circuit 130, and the other end of the output terminals of the second voltage divider circuit 130 may be connected to ground. Accordingly, Vout obtained by summing the output voltage of the first voltage divider circuit 120 and the output voltage of the second voltage divider circuit 130 may be output.

As the output voltage of the first voltage divider circuit 120 and the output voltage of the second voltage divider circuit 130 are summed and output, a high capacity output is possible and the first voltage divider circuit 120 and the second voltage divider circuit 130 respectively Since the output voltage is relatively low, capacitances of capacitors included in the first voltage divider circuit 120 and the second voltage divider circuit 130 may also be reduced. That is, as the voltage divider circuit is configured using a relatively low capacitance capacitor, the capacitance and size of the capacitor can be reduced, and problems such as ignition and heat generation can be reduced.

Meanwhile, the display device 100 includes a first resistor R1 having one end connected to the input terminal of the second voltage divider circuit 130, and a second resistor R2 having one end connected to the other end of the first resistor and the other end connected to the earth ground. ) and a first feedback circuit (IC1, PC1) for controlling the output of the power supply circuit 100 based on the voltage of one end of the second resistor.

For example, if Vin1 increases for some reason, the voltage applied to one end of the second resistor increases. When the voltage at one end of the second resistor increases, IC1 is turned on, and the PWM duty of the PWM IC is changed according to the secondary side light emission and primary side light receiving of PC1 to control Vin1.

Conversely, when Vin1 decreases, the voltage applied to one end of the second resistor decreases. When the voltage at one end of the second resistor decreases, IC1 is blocked or current flowing decreases, and the amount of light emitted from the secondary side of PC1 decreases or there is no light, so the PWM duty of the PWM IC is changed to control Vin1.

For feedback control as described above, values of the first resistor and the second resistor may be determined based on the conduction voltage of IC1 . For example, for feedback control when the voltage across one end of the second resistor is changed in both directions, the reference voltage is set with a predetermined margin on the conduction voltage, and the voltage across one end of the second resistor during normal operation is the reference voltage Values of the first resistor and the second resistor may be determined so that

This feedback operation controls only the input voltage of the second voltage divider circuit 130, and it is possible to simplify control and secure reliability. In addition, the output voltage can be compensated in the case of variable output voltage or sudden load change.

Meanwhile, the display device 100 further includes a third resistor R3 having one end connected to the other end of the first resistor and one end of the second resistor, and a first transistor Q9 connected to the other end of the third resistor. The transistor may change the voltage of one end of the second resistor based on the duty of a pulse width modulation (PWM) control signal input through a gate.

That is, while the first transistor is turned on, the resistance value decreases as the second resistor and the third resistor are connected in parallel, and the voltage across one end of the second resistor becomes lower. That is, the degree to which the voltage applied to one end of the second resistor is lowered may be changed by changing the duty cycle of the PWM control signal, and in this case, Vin1 may be changed through the above-described feedback operation. And, Vout can be changed according to the change of Vin1. In particular, unlike conventional voltage divider converters in which the step-down ratio is fixed to a multiple of 2, output voltages of various sizes can be provided according to duty changes of the PWM control signal.

For example, when the duty of the PWM control signal is increased, the voltage applied to one end of the second resistor is lowered, and Vin1 is increased through the feedback circuit, so that Vout is increased. Alternatively, when the duty cycle of the PWM control signal is decreased, the voltage applied to one end of the second resistor is increased, and Vin1 is decreased through the feedback circuit, thereby reducing Vout.

Here, values of the first resistor, the second resistor, and the third resistor may be determined based on the basic duty of the PWM control signal. For example, based on the case where the duty cycle of the PWM control signal is 50%, the reference voltage (a conduction voltage + a predetermined margin) of IC1 is determined, and the values of the first resistor, the second resistor, and the third resistor are determined therefrom. can That is, during normal operation, the duty cycle of the PWM control signal is 50%, and the output voltage can be controlled by increasing or decreasing the duty cycle of the PWM control signal.

4 is a diagram for specifically explaining the configuration of a display device 100 according to another embodiment of the present disclosure.

FIG. 4 is almost similar to FIG. 3 , but the difference is that a feedback circuit or the like is connected to the first voltage divider circuit 120 . Specifically, the other end of the output end of the first voltage divider circuit 120 is connected to a ground different from the earth ground, and the display device 100 includes a fourth resistor R1, one end of which is connected to the input end of the first voltage divider circuit 120; A fifth resistor R2 having one end connected to the other end of the fourth resistor and the other end connected to a ground different from the earth ground, and a second control output of the power supply circuit 100 based on a voltage of one end of the fifth resistor. Feedback circuits IC1 and PC1 may be further included.

In addition, the display device 100 further includes a sixth resistor R3 having one end connected to the other end of the fourth resistor and one end of the fifth resistor, and a second transistor Q9 connected to the other end of the sixth resistor. The transistor may change the voltage of one end of the fifth resistor based on the duty cycle of the PWM control signal input through the gate.

Here, since the feedback operation and the operation of changing Vout are the same as those of FIG. 3, duplicate descriptions are omitted.

Unlike FIG. 3 , in FIG. 4 , two types of voltages may be output. Specifically, the display device 100 of FIG. 4 fixes the variable output voltage Vout2 obtained by summing the output voltages of the first voltage divider circuit 120 and the second voltage divider circuit 130 as well as the second voltage divider circuit 130. An output voltage Vout1 may be additionally output.

5 is a diagram specifically illustrating a configuration of a display device 100 according to another embodiment of the present disclosure.

As shown in FIG. 5 , the power supply circuit 110 includes a first sub power supply circuit and a second sub power supply circuit, and the first voltage divider circuit 120 provides a voltage supplied from the first sub power supply circuit. The second voltage divider circuit 130 may divide and output the voltage supplied from the second sub power supply circuit.

In this case, there is an advantage in that temperature sharing is possible through the first sub power supply circuit and the second sub power supply circuit.

In FIG. 6 , Q1 to Q8 denote transistors included in the first voltage divider circuit 120 and the second voltage divider circuit 130 in FIGS. 3 to 5 . Q1 to Q4 are transistors included in the second voltage divider circuit 130, Q5 to Q8 are transistors included in the first voltage divider circuit 120, PWM_A is a signal for controlling Q1 and Q3, and PWM_B is a signal for controlling Q2 and Q3. A signal for controlling Q4, PWM_C is a signal for controlling Q5 and Q7, and PWM_D is a signal for controlling Q6 and Q8.

The upper part of FIG. 6 shows a case without a phase difference, and the lower part of FIG. 6 shows a case with a phase difference according to the present disclosure.

That is, the first voltage divider 120 may be controlled based on PWM_C and PWM_D obtained by inverting PWM_C, and the second voltage dividing circuit 130 may be controlled based on PWM_A and PWM_B obtained by inverting PWM_A.

In addition, the cycle (T) of PWM_C is equal to the cycle of PWM_A, and the preset phase difference may be greater than or equal to -T/4 and less than or equal to T/4. For example, a phase difference between PWM_A and PWM_C is T/4, and thus a phase difference between PWM_B and PWM_D may be T/4.

Effects of this operation are described in FIG. 7 .

The left side of FIG. 7 is the result of the same control as the upper part of FIG. 6, and the right side of FIG. 7 is the result of the same control as the lower part of FIG.

The uppermost graph on the left and right sides of FIG. 7 is the output of the first voltage divider circuit 120, and the second graph is the output of the second voltage divider circuit 130. And, the third graph shows the summed output Vout. That is, even if the control method for reducing the ripple is used, the outputs of the first voltage divider circuit 120 and the second voltage divider circuit 130 do not change, but the sum of the two outputs Vout has a reduced ripple. According to the example of FIG. 7 , since the ripple is reduced by about half, an output voltage with improved quality can be provided.

First, the power supply circuit supplies voltage (S810). Then, the first voltage divider circuit divides the voltage, and the second voltage divider circuit connected in series with the output terminal of the first voltage divider circuit divides the voltage (S820). Then, an output voltage based on the first output voltage of the first voltage divider circuit and the second output voltage of the second voltage divider circuit is provided (S830).

Here, one end of the output terminals of the first voltage divider circuit may be connected to one of the output terminals of the second voltage divider circuit, and the other end of the output terminals of the second voltage divider circuit may be connected to the ground.

The display device further includes a first resistor having one end connected to the input terminal of the second voltage divider circuit, a second resistor having one end connected to the other end of the first resistor and the other end connected to ground, and a first feedback circuit. In the step S830, the first feedback circuit may control the output of the power supply circuit based on the voltage of one end of the second resistor.

Here, the display device further includes a third resistor having one end connected to the other end of the first resistor and one end of the second resistor, and a first transistor connected to the other end of the third resistor, and controlling the output may include a gate of the first transistor. The voltage of one end of the second resistor may be changed based on the duty of a PWM (Pulse Width Modulation) control signal input through.

Meanwhile, the other end of the output end of the first voltage divider circuit may be connected to a ground different from the earth ground.

Here, the display device further includes a fourth resistor having one end connected to the input terminal of the first voltage divider circuit, a fifth resistor having one end connected to the other end of the fourth resistor and the other end connected to a ground different from the earth ground, and a second feedback circuit. In the providing step (S830), the second feedback circuit may control the output of the power supply circuit based on the voltage of one end of the fifth resistor.

The display device further includes a sixth resistor having one end connected to the other end of the fourth resistor and one end of the fifth resistor, and a second transistor connected to the other end of the sixth resistor, and controlling the output comprises a gate of the second transistor. It is possible to change the voltage of one end of the fifth resistor based on the duty of the PWM control signal input through .

In the step of dividing the voltage (S820), the first PWM signal is controlled based on the first PWM signal and the second PWM signal obtained by inverting the first PWM signal, and the third PWM signal has a predetermined phase difference with the first PWM signal. The second voltage divider circuit may be controlled based on the fourth PWM signal obtained by inverting the signal and the third PWM signal.

Here, the period T of the first PWM signal is equal to the period of the third PWM signal, and the predetermined phase difference may be greater than or equal to -T/4 and less than or equal to T/4.

Meanwhile, in the supplying step (S810), the first sub-power supply circuit and the second sub-power supply circuit included in the power supply circuit supply voltage, and in the voltage dividing step (S820), the first sub-power supply circuit includes the first sub-power supply circuit. The voltage supplied from the supply circuit may be divided and output, and the second voltage divider circuit may divide and output the voltage supplied from the second sub power supply circuit.

Meanwhile, according to an exemplary embodiment of the present disclosure, the various embodiments described above may be implemented as software including instructions stored in a machine-readable storage media (eg, a computer). can A device is a device capable of calling a stored command from a storage medium and operating according to the called command, and may include an electronic device (eg, the electronic device A) according to the disclosed embodiments. When a command is executed by a processor, the processor may perform a function corresponding to the command directly or by using other components under the control of the processor. An instruction may include code generated or executed by a compiler or interpreter. The device-readable storage medium may be provided in the form of a non-transitory storage medium. Here, 'non-temporary' only means that the storage medium does not contain a signal and is tangible, but does not distinguish whether data is stored semi-permanently or temporarily in the storage medium.

Also, according to an embodiment of the present disclosure, the method according to the various embodiments described above may be included in a computer program product and provided. Computer program products may be traded between sellers and buyers as commodities. The computer program product may be distributed in the form of a device-readable storage medium (eg compact disc read only memory (CD-ROM)) or online through an application store (eg Play Store™). In the case of online distribution, at least part of the computer program product may be temporarily stored or temporarily created in a storage medium such as a manufacturer's server, an application store server, or a relay server's memory.

In addition, according to one embodiment of the present disclosure, the various embodiments described above use software, hardware, or a combination thereof in a recording medium readable by a computer or similar device. can be implemented in In some cases, the embodiments described herein may be implemented in a processor itself. According to software implementation, embodiments such as procedures and functions described in this specification may be implemented as separate software modules. Each of the software modules may perform one or more functions and operations described herein.

Meanwhile, computer instructions for performing the processing operation of the device according to various embodiments described above may be stored in a non-transitory computer-readable medium. Computer instructions stored in such a non-transitory computer readable medium, when executed by a processor of a specific device, cause the specific device to perform processing operations in the device according to various embodiments described above. A non-transitory computer readable medium is a medium that stores data semi-permanently and is readable by a device, not a medium that stores data for a short moment, such as a register, cache, or memory. Specific examples of the non-transitory computer readable medium may include a CD, DVD, hard disk, Blu-ray disk, USB, memory card, ROM, and the like.

In addition, each of the components (eg, modules or programs) according to various embodiments described above may be composed of a single object or a plurality of entities, and some sub-components among the aforementioned sub-components may be omitted, or other sub-components may be used. Components may be further included in various embodiments. Alternatively or additionally, some components (eg, modules or programs) may be integrated into one entity and perform the same or similar functions performed by each corresponding component prior to integration. According to various embodiments, operations performed by modules, programs, or other components are executed sequentially, in parallel, iteratively, or heuristically, or at least some operations are executed in a different order, are omitted, or other operations are added. It can be.

Although the preferred embodiments of the present disclosure have been shown and described above, the present disclosure is not limited to the specific embodiments described above, and is common in the technical field belonging to the present disclosure without departing from the gist of the present disclosure claimed in the claims. Of course, various modifications and implementations are possible by those with knowledge of, and these modifications should not be individually understood from the technical spirit or perspective of the present disclosure.

Claims

In the display device,

power supply circuit;

a first voltage divider circuit including a plurality of capacitors and dividing and outputting the voltage supplied from the power supply circuit; and

A second voltage divider circuit including a plurality of capacitors and dividing and outputting the voltage supplied from the power supply circuit;

wherein an output end of the first voltage divider circuit and an output end of the second voltage divider circuit are connected in series to provide an output voltage based on a first output voltage of the first voltage divider circuit and a second output voltage of the second voltage divider circuit. Device.
According to claim 1,

One end of the output terminal of the first voltage divider circuit,

connected to one of the output terminals of the second voltage divider circuit;

The other end of the output end of the second voltage divider circuit,

A display device connected to earth ground.
According to claim 2,

a first resistor having one end connected to an input terminal of the second voltage divider circuit;

a second resistor having one end connected to the other end of the first resistor and the other end connected to the earth ground; and

A first feedback circuit for controlling an output of the power supply circuit based on the voltage of one end of the second resistor; further comprising a display device.
According to claim 3,

a third resistor having one end connected to the other end of the first resistor and one end of the second resistor; and

A first transistor connected to the other end of the third resistor; further comprising,

The first transistor,

A display device that changes a voltage of one end of the second resistor based on a duty of a pulse width modulation (PWM) control signal input through a gate.
According to claim 2,

The other end of the output end of the first voltage divider circuit,

A display device connected to a ground different from the earth ground.
According to claim 5,

a fourth resistor having one end connected to an input terminal of the first voltage divider circuit;

a fifth resistor having one end connected to the other end of the fourth resistor and the other end connected to a ground different from the earth ground; and

A second feedback circuit for controlling an output of the power supply circuit based on the voltage of one end of the fifth resistor; further comprising a display device.
According to claim 6,

a sixth resistor having one end connected to the other end of the fourth resistor and one end of the fifth resistor; and

A second transistor connected to the other end of the sixth resistor; further comprising,

The second transistor,

A display device that changes a voltage of one end of the fifth resistor based on a duty cycle of a PWM control signal input through a gate.
According to claim 1,

The first voltage divider circuit,

Controlled based on a first PWM signal and a second PWM signal obtained by inverting the first PWM signal;

The second voltage divider circuit,

A display device controlled based on a third PWM signal having a predetermined phase difference with the first PWM signal and a fourth PWM signal obtained by inverting the third PWM signal.
According to claim 8,

The period (T) of the first PWM signal is

The same as the period of the third PWM signal,

The preset phase difference is,

-T/4 or more and T/4 or less, a display device.
According to claim 1,

The power supply circuit,

a first sub power supply circuit; and

A second sub power supply circuit; includes,

The first voltage divider circuit,

Dividing and outputting a voltage supplied from the first sub power supply circuit;

The second voltage divider circuit,

A display device that divides and outputs a voltage supplied from the second sub power supply circuit.
In the control method of the display device,

supplying a voltage by a power supply circuit;

dividing the voltage by a first voltage divider circuit and dividing the voltage by a second voltage divider circuit having an output terminal connected in series to an output terminal of the first voltage divider circuit; and

and providing an output voltage based on the first output voltage of the first voltage divider circuit and the second output voltage of the second voltage divider circuit.
According to claim 11,

One end of the output terminal of the first voltage divider circuit,

connected to one of the output terminals of the second voltage divider circuit;

The other end of the output end of the second voltage divider circuit,

A control method connected to earth ground.
According to claim 12,

The display device,

a first resistor having one end connected to an input terminal of the second voltage divider circuit;

a second resistor having one end connected to the other end of the first resistor and the other end connected to the earth ground; and

A first feedback circuit; further comprising,

The step of providing,

The control method, wherein the first feedback circuit controls the output of the power supply circuit based on the voltage at one end of the second resistor.
According to claim 13,

The display device,

a third resistor having one end connected to the other end of the first resistor and one end of the second resistor; and

A first transistor connected to the other end of the third resistor; further comprising,

The step of controlling the output is,

The control method of changing the voltage of one end of the second resistor based on the duty of a PWM (Pulse Width Modulation) control signal input through the gate of the first transistor.
According to claim 12,

The other end of the output end of the first voltage divider circuit,

connected to a ground different from the earth ground.