KR100573121B1 - Muti-output power supply unit of plasma display device - Google Patents

Abstract

The present invention relates to a multi-output power supply of a plasma display device, comprising: a rectifier for transforming AC power from the outside supplied to the plasma display device into direct current; A transformer unit for transforming the DC power rectified through the rectifier into a predetermined output voltage; In the multi-output power supply of the plasma display device including a control unit for applying a pulse signal to the transformer unit to adjust the output voltage of the power output from the transformer, the transformer unit outputs a plurality of output voltage to the secondary side through a plurality of windings The control unit switches a pulse signal applied to the transformer unit through a voltage fed back from at least one output voltage of the plurality of output voltages of the transformer unit, and the plurality of output voltages depend on the switched pulse signal and the winding ratio of the transformer unit. And a plurality of output voltages of the transformer unit are supplied to at least one of a group consisting of an image processor, a logic controller, an address driver, a selected address power supply voltage, a scan electrode driver, and a sustain electrode driver of the plasma display apparatus.

Rectifier, transformer, control unit, DC-DC converter

Description

Multi-output power supply unit of plasma display device

1 is a circuit diagram showing a power supply of a conventional plasma display device.

2 is a schematic diagram of a controller for controlling a switching element of a power supply of a plasma display device.

3 is a circuit diagram showing an embodiment of a power supply device of a plasma display device according to the present invention.

Figure 4 is a circuit diagram showing another embodiment of the power supply of the plasma display device according to the present invention.

<Brief description of symbols for the main parts of the drawings>

210 ... rectifier

220.Transformer

230 control unit

R _VR ... Variable resistance

Vin ... Input Voltage

Vout ... output voltage

V1out ... first output voltage

V2out ... second output voltage

Vcc ... mains supply voltage

Va ... optional address voltage

The present invention relates to a multi-output power supply of a plasma display device, and more particularly, to generate a plurality of output voltages of the secondary side from a single input voltage of the primary side of the power supply of the plasma display device, The present invention relates to a multi-output power supply which converts again and supplies a voltage required by each driving device of the plasma display device.

A typical driving apparatus of the plasma display apparatus includes an image processor, a logic controller, an address driver, an X scan electrode driver, and a Y sustain electrode driver, and these drivers require respective power sources. The image processor converts an external analog image signal into a digital signal to generate an internal image signal. For example, the image processor generates 8-bit red (R), green (G), and blue (B) image data, a clock signal, and vertical and horizontal synchronization signals, respectively. The logic controller generates driving control signals S _A , S _Y , and S _X according to an internal image signal from the image processor. An address driving control signal S _A is processed among the driving control signals S _A , S _Y , and S _X from the address driving logic controller to generate a display data signal, and the generated display data signal is applied to the address electrode lines. Is authorized. The X scan electrode driver processes the X driving control signal S _X among the driving control signals S _A , S _Y , and S _X from the logic controller, and applies the X driving control signal S _X to the X electrode lines. The Y sustain electrode driver processes the Y driving control signal S _Y among the driving control signals S _A , S _Y , and S _X from the logic controller, and applies the Y driving control signal S _Y to the Y electrode lines.

The image processing unit, the logic control unit, the address driving unit, the X scan electrode driving unit, and the Y sustain electrode driving unit, which are the driving units of these plasma display apparatuses, require power voltages such as Vcc, Va, Vs, Vss log, and Vss sub.

1 is a circuit diagram showing a power supply of a conventional plasma display device. As shown, the power supply of the plasma display device includes a rectifier for converting AC power from the outside into direct current; A transformer unit for transforming the DC power rectified through the rectifier of the DC power rectified through the rectifier into an output voltage having a predetermined level; It includes a control unit for adjusting the output voltage of the power output from the transformer by applying a pulse signal to the transformer unit, it is composed of a combination of separate power supply device to generate power voltages required by the various driving unit.

AC voltages (V _{1 in} , V _{2 in} , ..., V _{n in} ) applied from the outside are converted into direct current through the rectifier 110 and the smoothing capacitor, respectively, and are configured as a switch mode power supply. Through the transformer 120, various DC voltages (V _{1 out} , V _{2 out} ,..., V _{n out} ) required for the driving units in the plasma display panel are converted and output. Here, a voltage distribution circuit and a switching element (eg, a MOS field effect transistor, an insulation gate, etc., so that each of the output DC voltages (V _{1 out} , V _{2 out} , ..., V _{n out} ) are kept constant. Voltage regulation switching is performed by a bipolar transistor, a thyristor, etc.). When the switching element starts the switching action, the energy of the alternating current is induced from the primary winding of the transformer to the secondary winding, and the energy induced in the secondary winding is the diode (D ₁ , D ₂ , ..., D _n ) and smoothing capacitors (C ₁₂ , C ₂₂ , ..., C _n2 ) are converted into DC power according to the turns ratio of the primary and secondary sides of the transformer to convert the first DC output voltage (V _{1 out} ) and 2 DC output voltage (V _{2 out} ) is to be output.

2 is a schematic diagram of a controller for controlling a switching element of a power supply of a plasma display device. The controller 130 is a part for controlling the output of a DC power of a predetermined value by driving a switch mode power supply by outputting a pulse width modulation waveform having a predetermined frequency and duty.

The DC power source changed in the smoothing capacitor operates a control unit that performs, for example, pulse width modulation through a starting resistor, and the switching element starts a switching action by the pulse width modulation waveform output from the control unit. When the switching element starts switching action, the energy of the alternating current is maintained from the primary winding of the transformer to one or more secondary windings, and the energy induced in the secondary winding is again converted into diodes (D ₁ , D ₂ , ... , D _n ) and smoothing capacitors (C ₁₂ , C ₂₂ , ..., C _n2 ) are converted into direct current power according to the turns ratio of the primary and secondary sides of the transformer to convert the first DC output voltage (V _{1 out} ). And a second DC output voltage V _{2 out} . Here, when the switch mode power supply normally outputs DC power, the controller 130 receives one or more output voltages as inputs and receives a control signal according to a change in the value thereof. That is, when the voltage output from the switch mode power supply increases, the duty of the waveform is reduced. On the contrary, when the voltage output from the switch mode power supply decreases, the duty of the waveform increases. It keeps the output voltage constant. The output voltages (Vcc, Va ...) are divided by the resistors (R ₁ , R ₂ , R _VR ) and applied to an integrated circuit including a zener diode. The error amount is compared by comparing the applied power supply voltage with a reference voltage. By applying to the control unit 130 of the primary side through the photocoupler to adjust the pulse width according to the output voltage to maintain a constant output voltage.

For example, if the reference voltage is 2.5V, the variable resistor R _VR is adjusted to maintain the divided voltage of the resistors R ₁ , R ₂ , and R _VR at 2.5V at all times. At this time, increasing the resistance lowers the output voltage of the switch mode power supply, and decreasing the resistance increases the output voltage.

However, the multi-output power supply of the conventional plasma display device has a significant manufacturing cost due to the inclusion of a rectifier, a transformer, a controller, and various high voltage resistance elements required for stabilizing the output voltage according to various power supply voltages. There was this.

In addition, there is a problem in that the development period is extended due to compliance with safety standards, changes in transformers and switch stresses in primary and secondary circuits, and output control circuits corresponding to input voltage variations.

Summary of the Invention The technical problem to be solved by the present invention is to solve the problems of the prior art and various other problems, and to reduce the number of circuit elements and the manufacturing cost of a transformer and a controller in a multi-output power supply of a plasma display device. There is a purpose.

The present invention relates to a multi-output power supply of the plasma display device for achieving the above object, and a rectifier for transforming the AC power from the outside supplied to the plasma display device into direct current; A transformer unit for transforming the DC power rectified through the rectifier into a predetermined output voltage; In the multi-output power supply of the plasma display device including a control unit for applying a pulse signal to the transformer unit to adjust the output voltage of the power output from the transformer, the transformer unit outputs a plurality of output voltage to the secondary side through a plurality of windings The control unit switches a pulse signal applied to the transformer unit through a voltage fed back from at least one output voltage of the plurality of output voltages of the transformer unit, and the plurality of output voltages depend on the switched pulse signal and the winding ratio of the transformer unit. It is characterized in that it occurs.

The plurality of output voltages of the transformer may be supplied to at least one of a group consisting of an image processor, a logic controller, an address driver, a selected address power supply voltage, a scan electrode driver, and a sustain electrode driver of the plasma display apparatus.

The plurality of output voltages are converted into a plurality of secondary DC voltages required by the plasma display apparatus through a plurality of DC-DC converters that convert the output voltage of the power supply into secondary DC voltages. The plasma display apparatus may be converted into a secondary DC voltage necessary for at least one of a group consisting of an image processor, a logic controller, an address driver, a selected address power supply voltage, a scan electrode driver, and a sustain electrode driver.

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

3 is a circuit diagram showing an embodiment of a power supply device of a plasma display device according to the present invention.

As shown in the figure, the multi-output power supply of the plasma display device according to the present invention, the rectifier 210 for transforming the AC power (V _in ) from the outside supplied to the plasma display device with a direct current; A transformer unit 220 for converting the DC power rectified by the rectifier 210 into an output voltage having a predetermined level and outputting the rectified voltage; The control unit 230 for applying a pulse signal to the transformer unit to adjust the output voltage of the power output from the transformer. The rectifier 210 rectifies the input commercial AC power in the bridge diode, converts the smoothing capacitor (C ₁ ) into DC power so that the power is induced in the primary winding of the transformer. The power supply from the rectifier 210 is applied to the control unit 230 for performing pulse width modulation, for example, through the smoothing capacitor C ₁ and the starting resistance. The control unit 230, which is supplied with power, outputs a predetermined pulse signal to the field effect transistor so that the field effect transistor starts the switching operation by the pulse width modulation waveform output from the control unit. When the field effect transistor starts the switching action, the energy of the alternating current is induced from the primary winding to the secondary winding of the transformer, and the energy induced into the secondary winding is again converted into a diode (D ₁ , D ₂ ) and a smoothing capacitor. Through the (C ₁₂ , C ₂₂ ) is converted into a DC power source according to the turns ratio of the primary and secondary side of the transformer is output to the first output voltage (V _{1 out} ) and the second output voltage (V _{2 out} ). As such, the controller 230 outputs a pulse width modulated waveform having a predetermined frequency and duty to drive the switch mode power supply so that the DC power of a predetermined value is output to the secondary side of the transformer.

On the other hand, the controller 230 reduces the duty of the waveform output when the voltage output from the switch mode power supply increases, and conversely increases the duty of the waveform when the voltage output from the switch mode power supply decreases. It keeps the output voltage of mode power supply at all times. Referring to FIG. 2, the output voltages Vcc, Va ... are divided by resistors R ₁ , R ₂ , and R _VR and applied to an integrated circuit including a zener diode, and the applied power supply voltage is referred to as a reference voltage. In comparison with the above, the error amount is applied to the control unit on the primary side through the photocoupler to adjust the pulse width according to the output voltage to keep the output voltage constant. For example, if the reference voltage is 2.5V, the variable resistor R _VR is adjusted to maintain the divided voltage of the resistors R ₁ , R ₂ , and R _VR at 2.5V at all times. At this time, increasing the resistance lowers the output voltage of the switch mode power supply, and decreasing the resistance increases the output voltage.

In the multi-output power supply of the plasma display device according to the present invention, the transformer 220 outputs a plurality of output voltages through a plurality of windings on the secondary side. The controller 230 switches a pulse signal applied to the transformer unit through a voltage fed back from at least one output voltage of the plurality of output voltages of the transformer unit, and the plurality of output voltages are switched pulse signals and winding ratios of the transformer unit. Occurs upon Preferably, in order to reduce the number of devices, the controller 230 may adjust a pulse signal applied to the transformer through a voltage fed back from one of the plurality of output voltages of the transformer. In the transformer unit 220, one winding of the primary side and a plurality of windings of the secondary side are made, so that each of the circuit elements on the primary side is sufficient, and the number of the transformer 220 and the controller 230 is also one. Complete with dog. Therefore, the number of circuit elements and the manufacturing cost of a transformer and a controller can be reduced.

The plurality of output voltages of the transformer 220 include Vcc, Va, Vs, Vss log, which are power voltages required for an image processor, a logic controller, an address driver, a selected address power supply voltage, a scan electrode driver, and a sustain electrode driver of the plasma display apparatus. It may be supplied at a power supply voltage such as Vss sub. If necessary, the plurality of output voltages are converted into a plurality of secondary DC voltages required by the plasma display apparatus through a plurality of DC-DC converters 241 and 242 that convert the output voltage of the power source into a secondary DC voltage. Can be. When it is difficult to generate various output voltages directly in the transformer 220, for example, after generating a voltage of about 3 ~ 5V, if necessary, through the DC-DC converter 241, the secondary DC voltage Vcc 5V and Vdd 3.3V Can produce

In one embodiment, when it is difficult to directly generate a 100 V output voltage in the transformer design, a second DC voltage Va is generated through the DC-DC converter 342 after generating a voltage that can be directly generated (eg, 120V). Can produce 100V.

So far, the present invention has been described with reference to the most preferred embodiments, but the above embodiments are only for better understanding of the present invention, and the contents of the present invention are not limited thereto. Additions, reductions, changes, modifications, etc. of some components of the composition of the present invention fall within the scope of the present invention as long as they belong to the technical idea of the present invention defined by the appended claims.

According to the multi-output power supply of the plasma display device according to the present invention, the number of transformers, high breakdown voltage switches, and controllers is reduced, and the manufacturing cost is significantly reduced. By regenerating various outputs using the output generated on the secondary side, The output voltages can be controlled without being affected by variations in the input voltage.

In addition, according to the multi-output power supply of the plasma display device according to the present invention, it is possible to improve the stability and reduce the defective device by reducing the number of transformers and the use of the primary switch element. In addition, in the plasma display panel driving apparatus configured with various output voltages, it is easy to cope with variations in the output voltage, and thus productivity may be greatly improved.

Claims (3)

A rectifier for transforming AC power from the outside supplied to the plasma display device into direct current; A transformer for converting the DC power rectified through the rectifier into an output voltage having a predetermined level and outputting the rectified voltage; In the multi-output power supply of the plasma display device including a control unit for applying a pulse signal to the transformer unit to adjust the output voltage of the power output from the transformer, The transformer unit outputs a plurality of output voltages through a plurality of windings on a secondary side, The controller switches a pulse signal applied to the transformer through a voltage fed back from at least one of the plurality of output voltages of the transformer, And the output voltages are generated according to the switched pulse signal and the winding ratio of the transformer. The method of claim 1, The plurality of output voltages of the transformer are supplied to at least one of a group consisting of an image processor, a logic controller, an address driver, a select address power supply voltage, a scan electrode driver, and a sustain electrode driver of the plasma display apparatus. Multi output power supply. The method of claim 1, The plurality of output voltages are converted into a plurality of secondary DC voltages required by the plasma display apparatus through a plurality of DC-DC converters that convert the output voltage of the power source into a secondary DC voltage. The plurality of secondary DC voltages are converted into secondary DC voltages required for at least one of a group consisting of an image processor, a logic controller, an address driver, a selected address power supply voltage, a scan electrode driver, and a sustain electrode driver of the plasma display apparatus. Multi-output power supply of the plasma display device.

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