Display apparatus and control method thereof

Abstract

A display device is disclosed. The display device includes a power supply circuit, a plurality of capacitors, a first voltage divider circuit that divides and outputs a voltage supplied from the power supply circuit, and a second voltage divider circuit that includes a plurality of capacitors and divides and outputs a voltage supplied from the power supply circuit. The output terminal of the first voltage divider circuit and the output terminal 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.

Description

Technology Field

[0001] The present disclosure relates to a display device and a method for controlling the same, and more specifically, to a display device that converts power and supplies power to each component and a method for controlling the same. Background Technology

[0002] With the introduction of self-emissive displays such as OLED TVs, DC converters for low-voltage, high-current loads are being developed.

[0003] Conventionally, as shown in FIG. 1a, a DC-DC converter circuit using a magnetic material (L1) has a problem in that the size of the inductor and heat generation increase significantly when the circuit is configured with a high capacity and high current. In addition, there are constraints on the size of components in order to manufacture a DC-DC converter circuit that is ultra-small and ultra-thin, but in the case of magnetic materials, there are no ultra-thin components, so it is difficult to manufacture an ultra-thin converter of about 6 mm or less.

[0004] Accordingly, as shown in FIG. 1b, a voltage divider converter using a capacitor (C1) instead of an inductor can be used. A voltage divider converter using a capacitor is a converter that can step up or step down voltage using a capacitor without a magnetic material. Since no magnetic material is used, it is possible to design a compact and ultra-thin form factor, and it has the characteristics of high efficiency and no heat generation.

[0005] Multi-layer ceramic capacitors (MLCCs) are used in voltage divider converters considering capacitance and size; however, there is a problem in that there are almost no high-capacitance MLCCs with a high withstand voltage of 100V or higher. In other words, applying high capacitance requires a significant increase in the number of parallel-connected MLCCs. Furthermore, due to the DC bias characteristic where capacitance decreases as the applied voltage increases, there is also the problem of having to select MLCCs with a withstand voltage margin of more than twice the required withstand voltage. Additionally, there are issues regarding Product Liability (PL) accidents, such as ignition and overheating caused by MLCC cracks, and the risk of PL accidents increases significantly as the voltage increases.

[0006] Due to the above problems, while many MLCCs with a voltage of 50V or less have been developed, high-capacity MLCCs with a voltage of 50V or more have hardly been developed.

[0007] 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, 4:1), and there is a problem in that the output voltage cannot be varied because the step-up and step-down ratios are fixed.

[0008] Accordingly, it is necessary to develop a circuit in which the above-mentioned problems are resolved. The problem to be solved

[0009] The present disclosure is in accordance with the aforementioned necessity, and the purpose of the present disclosure is to provide a display device capable of high-capacity DC-DC converting operation while using a conventional capacitor, and a control method thereof. means of solving the problem

[0010] According to one embodiment of the present disclosure for achieving the above objectives, a display device comprises a power supply circuit, a plurality of capacitors, a first voltage divider circuit that divides and outputs a voltage supplied from the power supply circuit, and a second voltage divider circuit that divides and outputs a voltage supplied from the power supply circuit, wherein the output terminal of the first voltage divider circuit and the output terminal 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.

[0011] In addition, one end of the output terminal of the first voltage divider circuit is connected to one end of the output terminal of the second voltage divider circuit, and the other end of the output terminal of the second voltage divider circuit can be connected to earth ground.

[0012] Additionally, it may further include a first resistor, one end of which is connected to the input terminal of the second voltage divider circuit, a second resistor, one end of which is connected to the other end of the first resistor and the other end of which is connected to ground, and a first feedback circuit that controls the output of the power supply circuit based on the voltage at one end of the second resistor.

[0013] Additionally, one end further includes a third resistor 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 can change the voltage at one end of the second resistor based on the duty cycle of a Pulse Width Modulation (PWM) control signal input through a gate.

[0014] In addition, the other end of the output terminal of the first voltage divider circuit may be connected to a ground different from the earth ground.

[0015] Additionally, it may further include a fourth resistor, one end of which is connected to the input terminal of the first voltage divider circuit; a fifth resistor, one end of which is connected to the other end of the fourth resistor and the other end of which is connected to a ground different from the earth ground; and a second feedback circuit that controls the output of the power supply circuit based on the voltage at one end of the fifth resistor.

[0016] In addition, one end further includes a sixth resistor 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 can change the voltage of one end of the fifth resistor based on the duty of a PWM control signal input through a gate.

[0017] Additionally, the first voltage divider circuit is controlled based on a first PWM signal and a second PWM signal in which the first PWM signal is inverted, and the second voltage divider circuit can be controlled based on a third PWM signal having a preset phase difference with the first PWM signal and a fourth PWM signal in which the third PWM signal is inverted.

[0018] And, the period (T) of the first PWM signal is the same as the period of the third PWM signal, and the preset phase difference may be greater than or equal to -T / 4 and less than or equal to T / 4.

[0019] Additionally, 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 the voltage supplied from the first sub-power supply circuit, and the second voltage divider circuit divides and outputs the voltage supplied from the second sub-power supply circuit.

[0020] Meanwhile, according to one embodiment of the present disclosure, a control method for a display device comprises the steps of: a power supply circuit supplying a voltage; a first voltage divider circuit dividing the voltage; a second voltage divider circuit connected in series with the output terminal of the first voltage divider circuit dividing the voltage; and providing 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.

[0021] In addition, one end of the output terminal of the first voltage divider circuit is connected to one end of the output terminal of the second voltage divider circuit, and the other end of the output terminal of the second voltage divider circuit can be connected to earth ground.

[0022] And, the display device further comprises a first resistor, one end of which is connected to the input terminal of the second voltage divider circuit, a second resistor, one end of which is connected to the other end of the first resistor and the other end of which is connected to the ground, and a first feedback circuit, wherein the first feedback circuit can control the output of the power supply circuit based on the voltage at one end of the second resistor.

[0023] Additionally, the display device further includes a third resistor connected to one end of 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 the step of controlling the output may change the voltage at one end of the second resistor based on the duty cycle of a Pulse Width Modulation (PWM) control signal input through the gate of the first transistor.

[0024] In addition, the other end of the output terminal of the first voltage divider circuit may be connected to a ground different from the earth ground.

[0025] Additionally, the display device further comprises a fourth resistor, one end of which is connected to the input terminal of the first voltage divider circuit, a fifth resistor, one end of which is connected to the other end of the fourth resistor and the other end of which is connected to a ground different from the earth ground, and a second feedback circuit, wherein the step of providing the second feedback circuit can control the output of the power supply circuit based on the voltage at one end of the fifth resistor.

[0026] In addition, the display device further includes a sixth resistor connected to one 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 the step of controlling the output can change the voltage of one end of the fifth resistor based on the duty of a PWM control signal input through the gate of the second transistor.

[0027] Additionally, the voltage dividing step may control the first voltage dividing circuit based on a first PWM signal and a second PWM signal in which the first PWM signal is inverted, and control the second voltage dividing circuit based on a third PWM signal having a preset phase difference with the first PWM signal and a fourth PWM signal in which the third PWM signal is inverted.

[0028] And, the period (T) of the first PWM signal is the same as the period of the third PWM signal, and the preset phase difference may be greater than or equal to -T / 4 and less than or equal to T / 4.

[0029] Additionally, the supplying step may involve a first sub-power supply circuit and a second sub-power supply circuit included in the power supply circuit supplying voltage, and the voltage dividing step may involve the first voltage dividing circuit dividing the voltage supplied from the first sub-power supply circuit and outputting it, and the second voltage dividing circuit dividing the voltage supplied from the second sub-power supply circuit and outputting it. Effects of the invention

[0030] According to various embodiments of the present disclosure as described above, a display device has a plurality of voltage divider converters connected in a cascade, so that high-capacity DC-DC converting operation is possible even when using MLCCs with relatively low capacitance.

[0031] In addition, the display device can reduce ripple by controlling multiple voltage divider converters using multiple PWM signals having a phase difference. Brief explanation of the drawing

[0032] FIGS. 1a and FIGS. 1b are drawings for explaining the prior art. FIG. 2 is a block diagram showing the configuration of a display device according to one embodiment of the present disclosure. FIG. 3 is a drawing for specifically explaining the configuration of a display device according to one embodiment of the present disclosure. FIG. 4 is a drawing for specifically describing the configuration of a display device according to another embodiment of the present disclosure. FIG. 5 is a drawing for specifically describing the configuration of a display device according to another embodiment of the present disclosure. FIG. 6 is a drawing illustrating a control method for reducing ripple according to one embodiment of the present disclosure. FIG. 7 is a drawing illustrating the results of a control method for reducing ripple according to one embodiment of the present disclosure. FIG. 8 is a flowchart illustrating a control method for a display device according to one embodiment of the present disclosure. Specific details for implementing the invention

[0033] The present disclosure will be described in detail below with reference to the attached drawings.

[0034] The terms used in the embodiments of this disclosure have been selected to be as widely used as possible, taking into account their functions within this disclosure; however, these terms may vary depending on the intent of those skilled in the art, case law, the emergence of new technologies, etc. Additionally, in specific cases, terms have been arbitrarily selected by the applicant, and in such cases, their meanings will be described in detail in the relevant explanatory section of this disclosure. Therefore, terms used in this disclosure should be defined not merely by their names, but based on their meanings and the overall content of this disclosure.

[0035] In this specification, expressions such as “have,” “may have,” “include,” or “may include” indicate the presence of such features (e.g., numerical values, functions, operations, or components such as parts) and do not exclude the presence of additional features.

[0036] The expression "at least one of A or / and B" should be understood as representing either "A" or "B" or "A and B".

[0037] Expressions such as "first," "second," "first," or "second" used in this specification may modify various components regardless of order and / or importance, and are used only to distinguish one component from another and do not limit said components.

[0038] The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, terms such as "comprising" or "consisting of" are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0039] In this specification, the term "user" may refer to a person using an electronic device or a device using an electronic device (e.g., an artificial intelligence electronic device).

[0040] Various embodiments of the present disclosure will be described in more detail below with reference to the attached drawings.

[0041] FIG. 2 is a block diagram showing the configuration of a display device (100) according to one 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).

[0042] The display device (100) can supply power to each component. For example, the display device (100) can 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 the power into multiple DC powers having multiple voltage levels and supply multiple DC powers to each of the multiple components inside the display device (100).

[0043] However, it is not limited to this, 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 is acceptable.

[0044] The power supply circuit (110) can generate power and supply the generated power to the first voltage divider circuit (120) and the second voltage divider circuit (130).

[0045] For example, the power supply circuit (Isolated Converter, 110) can 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).

[0046] The first voltage divider circuit (voltage divider converter (SC Converter), 120) includes a plurality of capacitors and can divide and output the voltage supplied from the power supply circuit (110).

[0047] For example, the first voltage divider circuit (120) may be implemented with a capacitor without including an inductor. The first voltage divider circuit (120) receives a voltage supplied from one of the outputs from the main winding and the auxiliary winding of the power supply circuit (110), and can divide the input voltage to output it.

[0048] The second voltage divider circuit (voltage divider converter (SC Converter), 130) includes a plurality of capacitors and can divide and output the voltage supplied from the power supply circuit (110).

[0049] For example, the second voltage divider circuit (130) may be implemented with a capacitor without including an inductor. The second voltage divider circuit (130) receives a voltage supplied from the other of the output from the main winding and the output from the auxiliary winding of the power supply circuit (110), and can divide the input voltage to output it.

[0050] 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) can provide an output voltage based on the first output voltage of the first voltage divider circuit (120) and the second output voltage of the second voltage divider circuit (130). For example, one end of the output terminal of the first voltage divider circuit (120) may be connected to one end of the output terminal of the second voltage divider circuit (130), and the other end of the output terminal of the second voltage divider circuit (130) may be connected to earth ground.

[0051] That is, the first voltage divider circuit (120) and the second voltage divider circuit (130) are 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 (reduction of the voltage withstand capability of the MLCC), and the size of each of the first voltage divider circuit (120) and the second voltage divider circuit (130) can be reduced. In addition, as the capacitance of the capacitors decreases, problems such as ignition and heat generation can be resolved.

[0052] According to one embodiment, the display device (100) may further include a first resistor, one end of which is connected to the input terminal of a second voltage divider circuit (130), a second resistor, one end of which is connected to the other end of the first resistor and the other end of which is connected to ground, and a first feedback circuit that controls the output of a power supply circuit (110) based on the voltage of one end of the second resistor.

[0053] Additionally, the display device (100) further includes a third resistor, one end of which is connected to the other end of a first resistor and one end of a second resistor, and a first transistor, the other end of which is connected to a first resistor. The first transistor can change the voltage at one end of the second resistor based on the duty cycle of a Pulse Width Modulation (PWM) control signal input through its gate. 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.

[0054] By changing the output voltage, output voltage compensation for sudden load changes is possible, and the problem of being unable to vary the output voltage in the past can be resolved. In addition, by controlling only the output voltage of the second voltage divider circuit (130), the control can be simplified and reliability ensured. The feedback operation and the operation of changing the output voltage will be explained in more detail through the drawings described later.

[0055] According to another embodiment, the other end of the output terminal of the first voltage divider circuit (120) may be connected to a ground different from earth ground. Additionally, the display device (100) may further include a fourth resistor, one end of which is connected to the input terminal of the first voltage divider circuit (120), a fifth resistor, one end of which is connected to the other end of the fourth resistor and the other end of which is connected to a ground different from earth ground, and a second feedback circuit that controls the output of the power supply circuit (110) based on the voltage at one end of the fifth resistor.

[0056] Additionally, the display device (100) further includes a sixth resistor, one end of which is connected to the other end of the fourth resistor and one end of the fifth resistor, and a second transistor, the other end of which is connected to the sixth resistor, and the second transistor can change the voltage at one end of the fifth resistor based on the duty of a PWM control signal input through the gate. 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.

[0057] This embodiment is almost identical to the embodiment described immediately prior, except that the output voltage of the first voltage divider circuit (120) is changed. In particular, with the output voltage of the second voltage divider circuit (130) connected to ground, the display device (100) can additionally output a fixed output voltage of the second voltage divider circuit (130) as well as a variable output voltage obtained by summing the output voltages of the first voltage divider circuit (120) and the second voltage divider circuit (130).

[0058] 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) may divide the voltage supplied from the first sub-power supply circuit and output it, and the second voltage divider circuit (130) may divide the voltage supplied from the second sub-power supply circuit and output it. In this case, there is an advantage that temperature sharing is possible through the first sub-power supply circuit and the second sub-power supply circuit.

[0059] Meanwhile, the first voltage divider circuit (120) is controlled based on a first PWM signal and a second PWM signal in which the first PWM signal is inverted, and the second voltage divider circuit (130) can be controlled based on a third PWM signal having a preset phase difference with the first PWM signal and a fourth PWM signal in which the third PWM signal is inverted. Here, the period (T) of the first PWM signal is the same as the period of the third PWM signal, and the preset phase difference may be greater than or equal to -T / 4 and less than or equal to T / 4. Through this operation, ripple can be reduced.

[0060] As described above, the display device (100) has a first voltage divider circuit (120) and a second voltage divider circuit (130) connected in a cascade, so that high-capacity DC-DC converting operation is possible even when configuring the voltage divider circuit using a capacitor of relatively low capacity.

[0061] In FIG. 2, for convenience of explanation, it is assumed that two voltage divider circuits, the first voltage divider circuit (120) and the second voltage divider circuit (130), are connected in a cascade, but this is not limited thereto. For example, the display device (100) may include three or more voltage divider circuits connected in a cascade.

[0062] The operation of the display device (100) will be described in more detail below through FIGS. 3 to 7. FIGS. 3 to 7 describe individual embodiments for the convenience of explanation. However, the individual embodiments of FIGS. 3 to 7 may be implemented in any combination.

[0063] FIG. 3 is a drawing for specifically explaining the configuration of a display device (100) according to one embodiment of the present disclosure.

[0064] The power supply circuit (110) supplies two power sources, Vin1 and Vin2, and the first voltage divider circuit (120) divides Vin2 and outputs it, and the second voltage divider circuit (130) divides Vin1 and outputs it.

[0065] One end of the output terminal of the first voltage divider circuit (120) is connected to one end of the output terminal of the second voltage divider circuit (130), and the other end of the output terminal of the second voltage divider circuit (130) can be connected to earth ground. Accordingly, Vout, which is the sum of the output voltage of the first voltage divider circuit (120) and the output voltage of the second voltage divider circuit (130), can be output.

[0066] As the output voltage of the first voltage divider circuit (120) and the output voltage of the second voltage divider circuit (130) are combined and output, a high-capacity output is possible, and since the output voltages of the first voltage divider circuit (120) and the second voltage divider circuit (130) are each relatively low, the capacitance of the capacitors included in the first voltage divider circuit (120) and the second voltage divider circuit (130) can also be reduced. That is, by configuring the voltage divider circuit using capacitors of relatively low capacitance, the capacitance and size of the capacitors can be reduced, and problems such as ignition and heat generation can be reduced.

[0067] Meanwhile, the display device (100) may further include a first resistor (R1) having one end connected to the input terminal of the second voltage divider circuit (130), a second resistor (R2) having one end connected to the other end of the first resistor and the other end connected to ground, and a first feedback circuit (IC1, PC1) that controls the output of the power supply circuit (100) based on the voltage at one end of the second resistor.

[0068] For example, if Vin1 increases for any reason, the voltage across one end of the second resistor increases. When the voltage across one end of the second resistor increases, IC1 conducts, and the PWM duty of the PWM IC changes according to the secondary side light emission and primary side light reception of PC1 to control Vin1.

[0069] Conversely, when Vin1 decreases, the voltage across one end of the second resistor decreases. When the voltage across one end of the second resistor decreases, IC1 is cut off or the current flowing through it decreases, and the amount of light emitted from the secondary side of PC1 decreases or stops, so the PWM duty of the PWM IC changes to control Vin1.

[0070] For feedback control as described above, the values ​​of the first resistor and the second resistor can be determined based on the conduction voltage of IC1. For example, for feedback control when the voltage applied to one end of the second resistor changes in both directions, a reference voltage can be set by providing a preset margin to the conduction voltage, and the values ​​of the first resistor and the second resistor can be determined such that the voltage applied to one end of the second resistor becomes the reference voltage during normal operation.

[0071] This feedback operation controls only the input voltage of the second voltage divider circuit (130), thereby simplifying the control and ensuring reliability. Additionally, the output voltage can be compensated in the case of variable output voltage or sudden load changes.

[0072] Meanwhile, the display device (100) further includes a third resistor (R3) 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, and the first transistor can change 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.

[0073] That is, while the first transistor is turned on, the resistance value decreases as the second and third resistors are connected in parallel, and the voltage across one end of the second resistor becomes lower. In other words, the degree to which the voltage across one end of the second resistor is lowered can be changed by changing the duty cycle of the PWM control signal, and in this case, Vin1 can be changed through the feedback operation described above. Furthermore, Vout can be changed according to the change in Vin1. In particular, unlike conventional voltage dividers where the step-up and step-down ratios are fixed as multiples of 2, various output voltages of different magnitudes can be provided depending on the change in the duty cycle of the PWM control signal.

[0074] For example, increasing the duty cycle of the PWM control signal lowers the voltage across one end of the second resistor, and through the feedback circuit, Vin1 increases, causing Vout to increase. Alternatively, decreasing the duty cycle of the PWM control signal increases the voltage across one end of the second resistor, and through the feedback circuit, Vin1 decreases, causing Vout to decrease.

[0075] Here, the values ​​of the first resistor, the second resistor, and the third resistor can be determined based on the basic duty of the PWM control signal. For example, the reference voltage of IC1 (conduction voltage + preset margin) can be determined based on the case where the duty of the PWM control signal is 50%, and the values ​​of the first resistor, the second resistor, and the third resistor can be determined from this. That is, during normal operation, the duty of the PWM control signal is 50%, and the output voltage can be controlled by increasing or decreasing the duty of the PWM control signal.

[0076] FIG. 4 is a drawing for specifically explaining the configuration of a display device (100) according to another embodiment of the present disclosure.

[0077] FIG. 4 is almost similar to FIG. 3, but differs in that a feedback circuit, etc., is connected to the first voltage divider circuit (120). Specifically, the other end of the output terminal of the first voltage divider circuit (120) is connected to a ground different from earth ground, and the display device (100) may further include a fourth resistor (R1) with one end connected to the input terminal of the first voltage divider circuit (120), a fifth resistor (R2) with one end connected to the other end of the fourth resistor and the other end connected to a ground different from earth ground, and a second feedback circuit (IC1, PC1) that controls the output of the power supply circuit (100) based on the voltage of one end of the fifth resistor.

[0078] Additionally, the display device (100) further includes a sixth resistor (R3) connected to one 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, and the second transistor can change the voltage of one end of the fifth resistor based on the duty of a PWM control signal input through the gate.

[0079] Here, the feedback operation and the operation to change Vout are the same as in FIG. 3, so redundant descriptions are omitted.

[0080] In FIG. 4, unlike FIG. 3, two types of voltages can be output. Specifically, the display device (100) of FIG. 4 can output not only a variable output voltage (Vout2) in which the output voltages of the first voltage divider circuit (120) and the second voltage divider circuit (130) are summed, but also an additional fixed output voltage (Vout1) of the second voltage divider circuit (130).

[0081] FIG. 5 is a drawing for specifically describing the configuration of a display device (100) according to another embodiment of the present disclosure.

[0082] As illustrated 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) divides the voltage supplied from the first sub-power supply circuit and outputs it, and the second voltage divider circuit (130) divides the voltage supplied from the second sub-power supply circuit and outputs it.

[0083] 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.

[0084] FIG. 6 is a drawing illustrating a control method for reducing ripple according to one embodiment of the present disclosure.

[0085] In FIG. 6, Q1 to Q8 represent transistors included in the first voltage divider circuit (120) and the second voltage divider circuit (130) in FIG. 3 to 5. Q1 to Q4 are transistors included in the second voltage divider circuit (130), and Q5 to Q8 are transistors included in the first voltage divider circuit (120). PWM_A is a signal for controlling Q1 and Q3, PWM_B is a signal for controlling Q2 and Q4, PWM_C is a signal for controlling Q5 and Q7, and PWM_D is a signal for controlling Q6 and Q8.

[0086] The top of FIG. 6 illustrates a case where there is no phase difference, and the bottom of FIG. 6 illustrates a case where there is a phase difference according to the present disclosure.

[0087] That is, the first voltage divider circuit (120) can be controlled based on PWM_C and PWM_D which is the inverted version of PWM_C, and the second voltage divider circuit (130) can be controlled based on PWM_A and PWM_B which is the inverted version of PWM_A.

[0088] Also, the period (T) of PWM_C is the same as the period 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, the phase difference between PWM_A and PWM_C is T / 4, and accordingly, the phase difference between PWM_B and PWM_D may be T / 4.

[0089] The effects of this operation are explained in Fig. 7.

[0090] FIG. 7 is a drawing illustrating the results of a control method for reducing ripple according to one embodiment of the present disclosure.

[0091] The left side of Fig. 7 is the result of the same control as the top of Fig. 6, and the right side of Fig. 7 is the result of the same control as the bottom of Fig. 6.

[0092] In the left and right of FIG. 7, the top graph represents the output of the first voltage divider circuit (120), and the second graph represents the output of the second voltage divider circuit (130). The third graph represents the summed output Vout. That is, even if a control method for reducing ripple is used, the outputs of the first voltage divider circuit (120) and the second voltage divider circuit (130) remain unchanged, but the summed output Vout of the two outputs has reduced ripple. According to the example of FIG. 7, the ripple is reduced by about half, thereby providing an output voltage of improved quality.

[0093] FIG. 8 is a flowchart illustrating a control method for a display device according to one embodiment of the present disclosure.

[0094] First, a power supply circuit supplies voltage (S810). Then, a first voltage divider circuit divides the voltage, and a second voltage divider circuit, with the output terminal of the first voltage divider circuit connected in series, 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).

[0095] Here, one end of the output terminal of the first voltage divider circuit is connected to one end of the output terminal of the second voltage divider circuit, and the other end of the output terminal of the second voltage divider circuit can be connected to earth ground.

[0096] And, the display device further comprises a first resistor, one end of which is connected to the input terminal of a second voltage divider circuit, a second resistor, one end of which is connected to the other end of the first resistor and the other end of which is connected to ground, and a first feedback circuit, and the step (S830) of providing the first feedback circuit can control the output of the power supply circuit based on the voltage of one end of the second resistor.

[0097] Here, the display device further includes a third resistor connected to one end of 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 the step of controlling the output can change the voltage of one end of the second resistor based on the duty of a Pulse Width Modulation (PWM) control signal input through the gate of the first transistor.

[0098] Meanwhile, the other end of the output terminal of the first voltage divider circuit may be connected to a ground different from earth ground.

[0099] Here, the display device further comprises a fourth resistor, one end of which is connected to the input terminal of the first voltage divider circuit, a fifth resistor, one end of which is connected to the other end of the fourth resistor and the other end of which is connected to a ground different from earth ground, and a second feedback circuit, and the step (S830) of providing the second feedback circuit can control the output of the power supply circuit based on the voltage of one end of the fifth resistor.

[0100] In addition, the display device further includes a sixth resistor connected to one 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 the step of controlling the output can change the voltage of one end of the fifth resistor based on the duty of a PWM control signal input through the gate of the second transistor.

[0101] Meanwhile, the voltage dividing step (S820) can control the first voltage dividing circuit based on the first PWM signal and the second PWM signal in which the first PWM signal is inverted, and control the second voltage dividing circuit based on the third PWM signal having a preset phase difference with the first PWM signal and the fourth PWM signal in which the third PWM signal is inverted.

[0102] Here, the period (T) of the first PWM signal is the same as the period of the third PWM signal, and the preset phase difference can be greater than or equal to -T / 4 and less than or equal to T / 4.

[0103] 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 voltage dividing circuit can divide the voltage supplied from the first sub-power supply circuit and output it, and the second voltage dividing circuit can divide the voltage supplied from the second sub-power supply circuit and output it.

[0104] According to various embodiments of the present disclosure as described above, a display device has a plurality of voltage divider converters connected in a cascade, so that high-capacity DC-DC converting operation is possible even when using MLCCs with relatively low capacitance.

[0105] In addition, the display device can reduce ripple by controlling multiple voltage divider converters using multiple PWM signals having a phase difference.

[0106] Meanwhile, according to the exemplary embodiments of the present disclosure, the various embodiments described above may be implemented as software comprising instructions stored on a machine-readable storage medium (e.g., a computer). The machine may include an electronic device (e.g., electronic device (A)) according to the disclosed embodiments, which is a device capable of calling instructions stored from the storage medium and operating according to the called instructions. When instructions are executed by a processor, the processor may perform a function corresponding to the instructions directly or by using other components under the control of the processor. Instructions may include code generated or executed by a compiler or an interpreter. The machine-readable storage medium may be provided in the form of a non-transitory storage medium. Here, "non-transitory" means only that the storage medium does not contain a signal and is tangible, and does not distinguish whether data is stored semi-permanently or temporarily on the storage medium.

[0107] Additionally, according to one embodiment of the present disclosure, the method according to the various embodiments described above may be provided as included in a computer program product. The computer program product may be traded between a seller and a buyer as a product. The computer program product may be distributed in the form of a device-readable storage medium (e.g., compact disc read-only memory (CD-ROM)) or online through an application store (e.g., Play Store™). In the case of online distribution, at least a portion of the computer program product may be temporarily stored or temporarily created in a storage medium such as the memory of a manufacturer's server, an application store's server, or a relay server.

[0108] Additionally, according to one embodiment of the present disclosure, the various embodiments described above may be implemented in a recording medium readable by a computer or a similar device using software, hardware, or a combination thereof. In some cases, the embodiments described herein may be implemented as the processor itself. According to 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.

[0109] Meanwhile, computer instructions for performing processing operations of the device according to the various embodiments described above may be stored in a non-transitory computer-readable medium. When computer instructions stored in such a non-transitory computer-readable medium are executed by the processor of a specific device, they cause the specific device to perform processing operations in the device according to the various embodiments described above. A non-transitory computer-readable medium refers to a medium that stores data semi-permanently and is readable 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 a non-transitory computer-readable medium may include CDs, DVDs, hard disks, Blu-ray discs, USBs, memory cards, ROMs, etc.

[0110] Additionally, each component (e.g., module or program) according to the various embodiments described above may be composed of a single or multiple entities, and some of the aforementioned sub-components may be omitted, or other sub-components may be further included in the various embodiments. Generally or additionally, some components (e.g., module or program) may be integrated into a single entity to perform the same or similar functions as those performed by each of the respective components prior to integration. The operations performed by the module, program, or other components according to the various embodiments may be executed sequentially, in parallel, iteratively, or heuristically, or at least some operations may be executed in a different order, omitted, or other operations added.

[0111] Although preferred embodiments of the present disclosure have been illustrated and described above, the present disclosure is not limited to the specific embodiments described above. It is understood that various modifications can be made by those skilled in the art without departing from the essence of the present disclosure as claimed in the claims, and such modifications should not be understood individually from the technical spirit or perspective of the present disclosure. Explanation of the symbols

[0112] 100: Display device 110: Power supply circuit 120: First voltage divider circuit 130: Second voltage divider circuit

Claims

Claim 1 A display device comprising: a power supply circuit; a first voltage divider circuit including a plurality of capacitors and outputting a voltage supplied from the power supply circuit by dividing the voltage; a second voltage divider circuit including a plurality of capacitors and outputting a voltage supplied from the power supply circuit by dividing the voltage; 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 ground; and a first feedback circuit controlling the output of the power supply circuit based on the voltage at one end of the second resistor; wherein one end of the output terminal of the first voltage divider circuit is connected to one end of the output terminal of the second voltage divider circuit, and the other end of the output terminal of the second voltage divider circuit is connected to ground, and the output terminal of the first voltage divider circuit and the output terminal 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. Claim 2 delete Claim 3 delete Claim 4 A display device according to claim 1, further comprising: a third resistor, one end of which is 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 changes 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. Claim 5 In claim 1, the other end of the output terminal of the first voltage divider circuit is connected to a ground different from the earth ground, a display device. Claim 6 A display device according to claim 5, further comprising: a fourth resistor, one end of which is connected to the input terminal of the first voltage divider circuit; a fifth resistor, one end of which is connected to the other end of the fourth resistor and the other end of which is connected to a ground different from the earth ground; and a second feedback circuit that controls the output of the power supply circuit based on the voltage at one end of the fifth resistor. Claim 7 A display device according to claim 6, further comprising: a sixth resistor, one end of which is 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 changes the voltage of one end of the fifth resistor based on the duty of a PWM control signal input through a gate. Claim 8 A display device according to claim 1, wherein the first voltage divider circuit is controlled based on a first PWM signal and a second PWM signal in which the first PWM signal is inverted, and the second voltage divider circuit is controlled based on a third PWM signal having a preset phase difference with the first PWM signal and a fourth PWM signal in which the third PWM signal is inverted. Claim 9 A display device according to claim 8, wherein the period (T) of the first PWM signal is the same as the period of the third PWM signal, and the preset phase difference is greater than or equal to -T / 4 and less than or equal to T / 4. Claim 10 A display device according to claim 1, wherein the power supply circuit comprises: 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 second voltage divider circuit divides and outputs a voltage supplied from the second sub-power supply circuit. Claim 11 A control method for a display device comprises: a step in which a power supply circuit supplies a voltage; a step in which a first voltage divider circuit divides the voltage, and a second voltage divider circuit, the output terminal of which is connected in series with the output terminal of the first voltage divider circuit, divides the voltage; and a step of providing 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; wherein the display device further comprises: a first resistor, one end of which is connected to an input terminal of the second voltage divider circuit; a second resistor, one end of which is connected to the other end of the first resistor and the other end of which is connected to ground; and a first feedback circuit; wherein the step of providing the output comprises the first feedback circuit controlling the output of the power supply circuit based on the voltage of one end of the second resistor, wherein one end of the output terminal of the first voltage divider circuit is connected to one end of the output terminal of the second voltage divider circuit, and the other end of the output terminal of the second voltage divider circuit is connected to ground. Claim 12 delete Claim 13 delete Claim 14 In claim 11, the display device further comprises: a third resistor, one end of which is 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 the step of controlling the output is a control method in which the voltage at one end of the second resistor is changed based on the duty of a Pulse Width Modulation (PWM) control signal input through the gate of the first transistor. Claim 15 ◈Claim 15 was abandoned upon payment of the registration fee.◈ In claim 11, the other end of the output terminal of the first voltage divider circuit is connected to a ground different from the earth ground, in a control method. Claim 16 ◈Claim 16 was abandoned upon payment of the registration fee.◈ In claim 15, the display device further comprises: a fourth resistor, one end of which is connected to the input terminal of the first voltage divider circuit; a fifth resistor, one end of which is connected to the other end of the fourth resistor and the other end of which is connected to a ground different from the earth ground; and a second feedback circuit; and the step provided is a control method in which the second feedback circuit controls the output of the power supply circuit based on the voltage of one end of the fifth resistor. Claim 17 ◈Claim 17 was abandoned upon payment of the registration fee.◈ In claim 16, the display device further comprises: a sixth resistor, one end of which is 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 the step of controlling the output is a control method that changes the voltage of one end of the fifth resistor based on the duty of a PWM control signal input through the gate of the second transistor. Claim 18 ◈Claim 18 was abandoned upon payment of the registration fee.◈ In claim 11, the voltage dividing step comprises a control method comprising controlling the first voltage dividing circuit based on a first PWM signal and a second PWM signal in which the first PWM signal is inverted, and controlling the second voltage dividing circuit based on a third PWM signal having a preset phase difference from the first PWM signal and a fourth PWM signal in which the third PWM signal is inverted. Claim 19 ◈Claim 19 was abandoned upon payment of the registration fee.◈ A control method according to Claim 18, wherein the period (T) of the first PWM signal is the same as the period of the third PWM signal, and the preset phase difference is greater than or equal to -T / 4 and less than or equal to T / 4. Claim 20 ◈Claim 20 was abandoned upon payment of the registration fee.◈ In claim 11, the supplying step comprises a first sub-power supply circuit and a second sub-power supply circuit included in the power supply circuit supplying voltage, and the voltage dividing step comprises the first voltage dividing circuit dividing and outputting the voltage supplied from the first sub-power supply circuit and the second voltage dividing circuit dividing and outputting the voltage supplied from the second sub-power supply circuit, a control method.

Images