KR20000041551A - Power supply circuit of a plasma display device - Google Patents

Abstract

PURPOSE: A power supply circuit of a plasma display device is provided to reduce a power consumption and a cost without using a power supply apparatus for a standby power. CONSTITUTION: A power supply circuit of a plasma display device comprises a switch(10) which switches an alternating current input voltage. A full wave rectification part(20) rectifies the AC input voltage transferred through the switch(10). A pulse width modulation(PWM) converter(30) PWM converts a voltage applied from the full wave rectification part(20) to generate powers(Vs,Va) for driving a plasma display panel and drive powers(Vcc1,Vcc2) for a standby mode. A controller(40) supplies the standby power(Vcc2) from the pulse width modulation(PWM) converter(30) to a battery(50), and generates first and second control signals(CS1,CS2). A power part(50) consists of a condenser(C1) for supplying a power for a PWM driving and a battery(BAT) for supplying a power for a controller driving. A comparison part(60) consists of first and second comparators(CM1,CM2), which compare voltages of the condenser(C1) and the battery(BAT) with a reference voltage respectively, and provides the comparison results to the controller(40). A first control part(70) is driven by the first control signal(CS1), and controls a driving of the PWM converter(30). A second control part(80) controls a supply of the voltages(Vs,Va) into a PDP driving circuit(90) from the PWM converter(30) in response to the control signal(CS2) from the controller(30).

Description

Power supply circuit of plasma display device

The present invention relates to a plasma display device, and more particularly, to a power supply circuit of a plasma display device capable of reducing standby power without providing a separate standby power supply circuit.

In general, the power supply circuit of the plasma display device provides a main power supply and a standby power supply separately to supply power only from the standby power supply in the standby mode, and the main power supply and standby in the operation mode of the plasma display device. Power was supplied using a power supply.

However, the conventional power supply of the plasma display device has a problem that the standby power due to the efficiency of the power supply in the standby mode is excessively consumed and a separate standby power supply must be provided.

The present invention is to solve the problems of the prior art as described above, and an object thereof is to provide a power supply circuit of a plasma display device that can reduce the cost down and power consumption without using a standby power supply device. .

1 is a detailed view of a power supply circuit of a plasma display device according to an embodiment of the present invention;

2 is a flowchart illustrating a power supply operation of a plasma display device according to an embodiment of the present invention;

(Explanation of symbols for the main parts of the drawing)

10 switching 20 full wave rectifier

30: PWM converter 40: controller

50: power supply unit 60: comparison unit

70: first control unit 80: second control unit

PC: Photo Coupler CM1, CM2: Comparator

Q1-Q3: Transistor ZD1: Zener Diode

R1, R2: Resistor C1: Capacitor

D1: diode

In order to achieve the above object of the present invention, according to an embodiment of the present invention, in the power supply circuit of the plasma display device for supplying power to the plasma display panel driving circuit, switching the AC input voltage Switch for; PWM converting the voltage input through the switch to supply power to the plasma display panel driving circuit, and a PWM converter for providing the first and second driving power for the standby mode; A controller for inputting a second standby power source applied from the PWM converter to generate first and second control signals; A power supply unit for storing a second standby power provided from the PWM converter through the controller; A comparison unit for comparing the potential of the power supply unit with a reference voltage and providing the result to the controller; A first control unit driven by a first control signal generated from the controller to control driving of the PWM converter; And a second control unit for supplying driving power from the PWM converter to the plasma display panel driving circuit by a second control signal generated from the controller.

The power supply circuit of the plasma display device of the present invention further includes a full-wave rectifier for full-wave rectifying the AC input provided to the PWM converter through the switch.

The power supply unit includes a power supply battery for storing the second standby power supplied from the PWM converter through the controller and a capacitor for storing the second standby power provided from the PWM converter through the controller. .

The comparator includes: a first comparator for comparing a potential of the battery with a reference voltage and providing a result to the controller; And a second comparator for comparing the potential of the capacitor with the reference voltage and providing the result to the controller.

The large controller inputs a comparison signal from the first comparator and generates a first control signal for turning off the PWM converter when the potential of the capacitor is higher than the reference voltage. In addition, the controller outputs a second control signal for driving the second control unit when a power-on signal is input from the outside, and inputs a comparison signal from the second comparator, when the potential of the battery is higher than the reference voltage. Generate a second control signal to drive.

The first controller is connected between a transistor to which a first control signal from the controller is applied to a gate, the emitter is grounded, and an output terminal of a PWM converter for applying the collector and the first and second standby power supplies of the transistor. It consists of a coupler.

The second control unit includes a transistor to which the second control signal from the controller is applied to the gate and the emitter is grounded; A second transistor connected to a collector of the transistor, a emitter connected to the PWM converter, and a collector connected to the PDP driving circuit; A resistor and a Zener diode are connected between the collector of the first transistor and the base of the second transistor.

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

1 shows a detailed view of a power supply circuit of a plasma display device according to an embodiment of the present invention.

1 is a power supply circuit of a plasma display device according to an embodiment of the present invention includes a switch 10 for switching an AC input voltage; Full-wave rectifying unit 20 for full-wave rectifying the AC input voltage through the switch 10, and power supply for driving the plasma display panel by PWM converting the voltage applied from the full-wave rectifying unit 20 (Vs, Va) And a PWM converter 30 for generating the driving power supplies Vcc1 and Vcc2 for the standby mode; A controller (40) for providing standby power (Vcc2) applied from the PWM converter (30) to the battery (50) and generating first and second control signals (CS1, CS2); A power supply unit 50 including a capacitor C1 for supplying the PWM driving power and a battery BAT for supplying the power for driving the controller 40; The first and second comparators CM1 and CM2 for comparing the potential of the capacitor C1 and the battery BAT of the power supply unit 50 with the reference voltage, respectively, and providing the result to the controller 40. Comparing unit 60 composed of; A first controller 70 driven by a first control signal CS generated from the controller 40 to control driving of the PWM converter 30; By the second control signal CS2 generated from the controller 40 to the second control unit 80 for controlling the supply of power (Vs, Va) from the PWM converter 30 to the PDP driving circuit 90 Is done.

The large controller inputs a comparison signal from the first comparator and generates a first control signal for turning off the PWM converter when the potential of the capacitor is higher than the reference voltage. When the potential is higher than the reference voltage, a second control signal for driving the second control unit is generated.

The first controller 70 includes a transistor Q1 having a first control signal CS1 from the controller 40 applied to a gate, and having an emitter grounded, a collector of the transistor Q1 and a first and The photo coupler PC is connected between the second standby power supplies Vcc1 and Vcc2.

The second controller (80) includes a transistor (Q2) having a second control signal (CS2) from the controller (40) applied to the gate and the emitter grounded. A transistor Q3 connected to a base of the transistor Q2, an emitter connected to the PWM converter 30, and a collector connected to the PDP driving circuit 90, and a transistor Q2 of the transistor Q2. A resistor R1 and a Zener diode ZD1 are connected between the collector and the base of the transistor Q3.

Referring to the operation of the power supply circuit of the plasma display device of the present invention as described above based on the flowchart of FIG.

When the first AC power is applied by the turn-on of the switch 10 to supply power to the plasma display device (step 101), the PWM converter 30 converts the full-wave rectified voltage through the full-wave rectifier 20 into a controller. The driving voltage Vcc2 is applied to the 40 (step 102), and the controller 40 applies the driving voltage Vcc2 provided from the PWM converter 30 to the power supply unit 50. The driving voltage ( Vcc2 is provided as a backup battery BAT for driving the controller 40 so that the potential of the battery BAT is gradually increased, and at the same time, the driving voltage Vcc2 is applied to the first control unit 70 of the power supply unit 50. It is supplied to a capacitor C1 for supplying power for driving the photo coupler and charged.

At this time, the controller 40 detects a power-on signal (not shown in the figure) of the plasma display element applied from the outside (step 103), and drives the PDP driving circuit 90 when the power-on signal is input. Therefore, the controller 40 generates the second control signal CS2 to the second controller 80 (step 104), thereby driving the transistors Q2 and Q3 of the second controller 80 to convert the PWM. The drive signals Vs and Va are generated by a driver that generates a signal for driving the plasma display panel from the step 30 (step 105).

The controller 40 then checks the power-on signal (step 106), and if the power-on signal persists, returns to step 102 and the conversion operation of the PWM converter 30 is continued in the manner described above. .

In step 106, when the power-on signal is checked and the power-on signal is turned off, the transistors Q2 and Q3 of the second control unit 80 are turned off by the second control signal CS2 from the controller 40 to turn off the PWM converter ( The driving voltages Vs and Va provided from the 30 to the PDP driving circuit 90 are cut off.

If no power-on signal is detected in step 103, operation is performed in the standby mode. Therefore, the potential of the battery BAT of the power supply unit 50 and the potential of the capacitor C1 are respectively compared with the reference voltage VR, which is a predetermined value (step 109), and when each potential is lower than the reference voltage, step 102 Return to to continue charging operation.

In step 109, if each potential is higher than the reference voltage VR, the controller 40 generates the first control signal CS1 to the first control unit 70 (step 110), and accordingly the first control unit 70 Transistor Q1 is driven to operate the photo coupler PC. Accordingly, the power applied to the PWM converter 30 is cut off and turned off (step 120), so that the plasma display device operates in the standby mode.

In the standby mode, the controller 40 checks whether the power-on signal is input (step 131), and when the power-on signal is input, the controller 40 determines whether the first control unit 70 is controlled by the first control signal CS from the controller 40. The transistor Q1 is turned off (step 132), and thus the photo coupler PC is turned off (133). The controller 40 generates a second control signal CS to the second controller 80 (step 134) to drive the transistors Q2 and Q3, thereby operating the PDP driving circuit 90. Driving voltages Vs and Va are generated.

On the other hand, if the power-on signal is not detected in step 131, the flow goes to step 137 to compare the battery BAT potential of the power supply unit 50 and the potential of the capacitor C1 with the reference voltage VR, and as a result of the comparison, the power supply unit 50 If the potential of the battery is lower than the set value, go to step 102 to drive the PWM converter 30 to charge the battery BAT to the desired level. If the battery potential is at the set value, the flow proceeds to step 130 to continue the standby mode.

As described in detail above, according to the present invention, the PDP driving the built-in backup battery using only the main power circuit by controlling the interest sequence by controlling the main power circuit and the microcomputer (controller) without separately providing a standby mode power circuit. There is an advantage to supply power. In addition, there is an advantage that can reduce the cost and power consumption by effectively controlling the standby mode power supply.

In addition, this invention can be implemented in various changes within the range which does not deviate from the summary.

Claims (8)

In the power supply circuit of the plasma display device for supplying power to the plasma display panel drive circuit, A switch for switching the AC input voltage; PWM converting the voltage input through the switch to supply power to the plasma display panel driving circuit, and a PWM converter for providing the first and second driving power for the standby mode; A controller for inputting a second standby power source applied from the PWM converter to generate first and second control signals; A power supply unit for storing a second standby power provided from the PWM converter through the controller; A comparison unit for comparing the potential of the power supply unit with a reference voltage and providing the result to the controller; A first control unit driven by a first control signal generated from the controller to control driving of the PWM converter; And a second control unit for supplying driving power from the PWM converter to the plasma display panel driving circuit by a second control signal generated from the controller. The power supply circuit of claim 1, further comprising a full-wave rectifier for full-wave rectifying the AC input provided to the PWM converter through the switch. The power supply battery of the controller for storing the second standby power provided from the PWM converter through the controller and the second standby power provided from the PWM converter through the controller. A power supply circuit for a plasma display device, characterized by comprising a capacitor for storing. 4. The apparatus of claim 3, wherein the comparison unit comprises: a first comparator for comparing a potential of the battery and a reference voltage and providing a result to the controller; And a second comparator for comparing the potential of the capacitor with the reference voltage and providing the result to the controller. 5. The plasma display of claim 4, wherein the large controller inputs a comparison signal from a first comparator and generates a first control signal for turning off the PWM converter when the potential of the capacitor is higher than the reference voltage. Power supply circuit of the device. The battery of claim 4, wherein the controller outputs a second control signal for driving the second control unit when a power-on signal is input from the outside, and inputs a comparison signal from the second comparator so that the potential of the battery is higher than a reference voltage. And generating a second control signal for driving the second control unit. 2. The PWM converter of claim 1, wherein the first controller is configured to apply a first control signal from the controller to a gate and to emit a ground of an emitter, a collector of the transistor, and first and second standby power supplies. The power supply circuit of the plasma display device, characterized in that consisting of a photo coupler connected between the output terminal of the. The method of claim 1, wherein the second control unit A transistor to which a second control signal from the controller is applied to the gate and the emitter is grounded; A second transistor connected to a collector of the transistor, a emitter connected to the PWM converter, and a collector connected to the PDP driving circuit; And a Zener diode and a resistor connected between the collector of the first transistor and the base of the second transistor.