KR101672538B1 - Driving circuit compatible with electronic or magnetic ballast and LED(Light Emitting Diode) fluorescent lamp comprising the same - Google Patents

Abstract

The technical idea of the present invention is to provide an electric or magnetic ballast which can be compatible with existing electric and magnetic ballasts and stably lights up the LED light sources constituting the LED fluorescent lamp and can change the array structure of the LED light sources, An LED fluorescent lamp including a compatible driving circuit and a driving circuit thereof is provided. The compatible driving circuit includes a pre-voltage driver connected to an output terminal of the electronic or magnetic ballast and controlling resonance of the inductance L and the capacitance C of the ballast; A rectifier connected to the preliminary voltage driver and rectifying the AC voltage to a DC voltage using a bridge diode; A load voltage determination unit connected to the rectification unit and configured to delay the connection of the load until the output of the rectification unit reaches a predetermined first voltage so that the output voltage of the stabilizer rises; And a voltage current regulator connected to the output terminal of the load voltage determination unit (or the input terminal of the load) and the output terminal of the load, for adjusting the voltage and current applied to the load.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an LED fluorescent lamp including a driving circuit and a driving circuit,

TECHNICAL FIELD The present invention relates to a lighting apparatus, and more particularly to a driving circuit for an LED fluorescent lamp and an LED fluorescent lamp including the driving circuit.

Recently, various lighting fixtures including fluorescent lamps are being replaced with LEDs having similar appearance, capable of sharing sockets, and having high efficiency for energy saving. However, since existing fluorescent lamp stabilizers are built in existing fluorescent lamp fixtures, it is inconvenient to replace fluorescent lamp stabilizers installed in conventional fluorescent lamp fixtures with LED converters in order to use general LED fluorescent lamps, The diffusion of fluorescent lamps is not activated. BACKGROUND ART [0002] The background art of the present invention is disclosed in Korean Patent Laid-Open Publication No. 10-2012-0130905 (2012.12.04) entitled " Introducing LED lamp illumination device ".

The technical idea of the present invention is to provide an LED light source that is compatible with existing magnetic and magnetic ballasts and that stably lights up the LED light sources constituting the LED fluorescent lamp and that changes the connection structure of the LED light sources in the LED light source array, A magnetic ballast compatible driving circuit and an LED fluorescent lamp including the driving circuit.

In order to solve the above problems, the technical idea of the present invention is to provide a pre-voltage driver connected to an output terminal of an electronic or magnetic ballast and controlling resonance of an inductance L and a capacitance C of the ballast; A rectifier connected to the preliminary voltage driver and rectifying the AC voltage to a DC voltage using a bridge diode; A load voltage determination unit connected to the rectification unit and configured to delay the connection of the load until the output of the rectification unit reaches a predetermined first voltage so that the output voltage of the stabilizer rises; And a voltage and current regulator connected to an output terminal of the load voltage determination unit (or an input terminal of the load) and an output terminal of the load, the voltage and current regulator being adapted to control a voltage and a current applied to the load. Lt; / RTI >

In one embodiment of the present invention, the preliminary voltage driving unit includes an input switch connected to the ballast output terminal and connecting the inductor of the ballast to a capacitor, and the load voltage determining unit may include a load switch for connecting the load Wherein the input switch remains on until the first voltage is reached, and when the first voltage is reached, the load switch is turned on to connect the load, and the input switch is turned off (Off).

In one embodiment of the present invention, the voltage current regulator includes a first resistor and a second resistor connected to the output terminal of the load voltage determining unit and connected in series to each other, a field effect transistor (FET) connected to the output terminal of the load, And a third resistor connected to the FET, an output terminal of the load is connected to a drain of the FET, a terminal between the first resistor and the second resistor is connected to a gate of the FET, The third resistor is connected to the second resistor, the gate voltage of the FET corresponds to a partial voltage of the output voltage of the ballast, the output voltage of the ballast rises, and the gate voltage of the FET is higher than the threshold voltage of the FET The FET is turned on to cause a current to flow through the load and the current flowing to the third resistor is sensed so that the current flowing to the load can be controlled.

In one embodiment of the present invention, the load is an LED light source array including a plurality of LED light sources, and the connection relationship of the LED light sources in the LED light source array is changed to adjust the current.

In one embodiment of the present invention, the electro-magnetic ballast-compatible drive circuit further includes an AC / DC buck converter connected to an output terminal of the load voltage determination unit, wherein the AC / The down output voltage is lowered to generate the down voltage, and the down voltage can be used to change the operation of the switch or the circuit connection relationship included in the electromagnetism-compatible ballast driving circuit.

According to an aspect of the present invention, there is provided an electronic or magnetic ballast for increasing a voltage and restricting an output current through resonance of an inductance and a capacitance; A preliminary voltage driver connected to an output terminal of the ballast to control the resonance; A rectifier connected to the preliminary voltage driver for rectifying an AC voltage to a DC voltage using a bridge diode; A load voltage determination unit connected to the rectification unit and configured to delay the connection of the load until the output of the rectification unit reaches a predetermined first voltage so that the output voltage of the stabilizer rises; A load connected to the load voltage determining unit and including a plurality of LED light sources; And a voltage current regulator connected to an output terminal of the load voltage determination unit (or an input terminal of the load) and an output terminal of the load, and configured to adjust voltage and current applied to the load.

In one embodiment of the present invention, the preliminary voltage driving unit includes an input switch connected to the ballast output terminal and connecting the inductor of the ballast to a capacitor, and the load voltage determining unit may include a load switch for connecting the load The input switch remains on until the first voltage is reached, and when the first voltage is reached, the load switch is turned on to connect the load, and the input switch can be turned off .

In one embodiment of the present invention, the load voltage determining unit may include two resistors connected in series between an output terminal of the rectifying unit and the ground, and may sense the voltage between the two resistors to reach the first voltage .

In one embodiment of the present invention, the voltage current regulator includes a first resistor and a second resistor connected to an output terminal of the load voltage determination unit and connected in series to each other, a FET connected to an output terminal of the load, And a resistor connected between a drain of the FET and an output terminal of the load, and a gate of the FET is connected to a terminal between the first resistor and the second resistor, The gate voltage of the FET corresponds to the partial voltage of the output voltage of the ballast, and when the output voltage of the ballast rises and the gate voltage of the FET becomes equal to or higher than the threshold voltage of the FET, The current flows to the load, the current flowing to the third resistor is sensed, and the current flowing to the load can be controlled.

In one embodiment of the present invention, the load has an LED light source array structure in which the LED light sources are connected to each other in at least one of a serial connection and a parallel connection, and the connection between the LED light sources in the LED light source array is a serial connection Or the parallel connection may be changed to a serial connection so that the current can be adjusted.

In one embodiment of the present invention, the preliminary voltage driving unit includes an input switch connected to the ballast output terminal for connecting the inductor of the ballast and the capacitor, and the load voltage determining unit includes a load switch for connecting the load Wherein the load includes at least two serial parallel switches for changing the connection between the LED light sources from a serial connection to a parallel connection or from a parallel connection to a serial connection, DC converter comprising: an AC / DC buck converter connected to an output stage, the AC / DC buck converter dropping an output voltage of the load voltage determiner to generate a DC down voltage, It can be used for driving a parallel switch.

In one embodiment of the present invention, the input switch, the load switch, and the serial / parallel switch may be implemented by a Bipolar Junction Transistor (BJT), a UniJunction Transistor (UJT), a Programmable Unijunction Transistor (PUT), a Junction Field Effect Transistor A thyristor of at least one of a metal oxide semiconductor FET, an insulated gate bipolar transistor (IGBT), a silicon controlled rectifier (SCR), a triac (TRIAC), and a gate turn off (GTO) Or a relay.

The LED fluorescent lamp including the driving circuit of the electric / magnetic ballast compatible type and the driving circuit thereof according to the technical idea of the present invention controls the output voltage of the ballast to rise up to a predetermined preliminary voltage through the preliminary voltage driving part, The output voltage of the ballast can be adjusted to be applied to the LED light source array after reaching the preliminary voltage. On the other hand, the voltage applied to the LED light source array can be controlled through the voltage and current control unit, and the connection relationship of the LED light sources in the LED light source array can be converted into serial or parallel connection. Accordingly, the LED fluorescent lamp including the compatible driving circuit of the present embodiment can stably light the LED light sources and keep the lighting stable, appropriately corresponding to the characteristics of various existing ballasts.

FIGS. 1A and 1B are circuit diagrams for explaining the function of a ballast connected to an electro-magnetic ballast compatible driving circuit according to an embodiment of the present invention.
2 is a circuit diagram of an LED fluorescent lamp including an electric / magnetic ballast compatible driving circuit according to an embodiment of the present invention.
FIG. 3 is a flow chart showing an operation procedure of the electric / magnetic ballast compatible driving circuit in the LED fluorescent lamp of FIG. 2;
4A and 4B are circuit diagrams illustrating a structure of the LED fluorescent lamp of FIG. 3 in which the LED light source array is connected in series with the structure in which the LEDs are connected in parallel via the serial parallel switch.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments of the present invention are described in order to more fully explain the present invention to those skilled in the art, and the following embodiments may be modified in various other forms, The present invention is not limited to the embodiment. Rather, these embodiments are provided so that this disclosure will be more thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

In the following description, when an element is described as being connected to another element, it may be directly connected to another element, but a third element may be interposed therebetween. Similarly, when an element is described as being on top of another element, it may be directly on top of the other element, and a third element may be interposed therebetween. In addition, the structure and size of each constituent element in the drawings are exaggerated for convenience and clarity of description, and a part which is not related to the explanation is omitted. Wherein like reference numerals refer to like elements throughout. It is to be understood that the terminology used is for the purpose of describing the present invention only and is not used to limit the scope of the present invention.

1A and 1B are circuit diagrams for explaining the function of a ballast connected to an electro-magnetic ballast compatible driving circuit according to an embodiment of the present invention. FIG. 1A shows a pre-heat process, 1b represent the ignition process.

Referring to FIGS. 1A and 1B, generally, the ballast can be broadly divided into an electromagnetic type and a magnetic type. Such a ballast can generate electric energy that can heat the filament F of the fluorescent lamp by the resonance by the inductor L of the output portion and the capacitor C2. In the case of a conventional fluorescent lamp, this process is referred to as preheating, and if the discharge of the fluorescent lamp is performed through the preheating process, the current of the lamp may increase, and the voltage of the lamp may decrease. Such a negative resistance characteristic may cause unstable lighting or breakage of the lamp, so that the ballast can function to limit the current when the voltage of the lamp reaches a certain operating voltage.

The flow of current in the preheating process of FIG. 1A is performed by the inductor L, the left filament F1, the second capacitor C2, the right filament F2, 1 < / RTI > capacitor C1. In addition, resonance due to the inductance of the inductor L and the combined capacitance of the first and second capacitors C1 and C2 may occur, and the voltage gain at resonance may have a large value close to approximately 100. [

When the filament (F1, F2) is preheated by the preheating process, the fluorescent lamp starts to flow current through the discharge tube, which is referred to as "discharging" or "lighting" the fluorescent lamp.

The flow of current in the discharge process of FIG. 1B can be represented by two paths as shown by arrows. The first path I1 is the inductor L → the left filament F1 → the second capacitor C2 → the right filament F2 → the first capacitor C1. In the second path (I2), if the impedance value in the discharge tube is R _Im , the second capacitor (C2) -> R _Im to be. The path that the actual fluorescent lamp generates light is the second path (I2), and the ideal voltage gain can be around 1.

The ballast connected to the electro-magnetic ballast compatible driving circuit (hereinafter, referred to as a 'compatible driving circuit') of the present embodiment may also be subjected to a process corresponding to the preheating process and the discharging process. However, the compatible driving circuit of this embodiment is a circuit used for lighting the LED fluorescent lamp, so that the filament may not actually be preheated or discharged. Therefore, in the compatible driving circuit of the present embodiment, the preheating process corresponds to a process in which the voltage rises due to the resonance between the inductor and the capacitor to reach the preliminary voltage, and the discharging process corresponds to the load of the compatible driving circuit It is possible to cope with the process of lighting the LED light sources.

2 is a circuit diagram of an LED fluorescent lamp including an electric / magnetic ballast compatible driving circuit according to an embodiment of the present invention.

Referring to FIG. 2, the LED fluorescent lamp 1000 of the present embodiment may include a ballast 100, a compatible driving circuit, and an LED light source array 700.

As described above with reference to FIGS. 1A and 1B, the ballast 100 can perform a voltage raising function through resonance between the inductor 110 and the capacitor 120, and a current limiting function after the turn on. The ballast 100 may be of any type, e.g., electronic or magnetic. The specific structure of the ballast 100 is already known, so only the inductor 110 and the capacitor 120 are shown for convenience.

The compatible drive circuit includes a pre-voltage driver 200, a rectifier 300, a load voltage determiner 400, an AC / DC buck converter 500, and a voltage / current regulator 600. The pre- . ≪ / RTI >

The preliminary voltage driver 200 may be connected to the output terminal of the ballast 100 and may include two input switches 230 and 250. The first input switch 230 of the two input switches may function to connect the inductor 110 and the capacitor 120 of the ballast 100 with each other. The second input switch 250 of the two input switches also functions to electrically connect the inductor 110 and the capacitor 120. However, the second input switch 250 functions to provide an electrical path rather than directly connecting the inductor 110 and the capacitor 120 .

The first input switch 230 is connected to the first bridge switch 310 of the rear stage rectifier 300 and the second input switch 250 is connected to the second bridge of the rectifier 300, And may be connected to a diode 330.

The first and second input switches 230 and 250 can be maintained in an ON state in the process of raising the voltage due to the resonance between the inductor 110 and the capacitor 120. [ In the compatible driving circuit of the present embodiment, the first and second input switches 230 and 250 can keep the ON state as a default. Accordingly, when power is input to the ballast 100, the process of raising the voltage due to the resonance can proceed immediately. On the other hand, when the first and second input switches 230 and 250 are turned off, the output current pattern of the ballast 100 is changed from the current pattern after the pre-heat process of the conventional fluorescent lamp, . ≪ / RTI > Accordingly, in the compatible driving circuit of this embodiment, the process of raising the output voltage of the ballast 100 to the preliminary voltage can cope with the preheating process of the existing fluorescent lamp, and thus the conventional electronic or magnetic ballast can be used as it is have.

The first and second input switches 230 and 250 may be implemented through various devices capable of performing a switching function. For example, the first and second input switches 230 and 250 may be a Bipolar Junction Transistor (BJT), a UniJunction Transistor (UJT), a Programmable Unijunction Transistor (PUT), a Junction Field Effect Transistor (JPET), a Metal Oxide Semiconductor FET , And IGBT (Insulated Gate Bipolar Transistor). The first and second input switches 230 and 250 may be implemented as a thyristor such as a Silicon Controlled Rectifier (SCR), a TRIAC, and a Gate Turn Off (GTO) . ≪ / RTI >

The output voltage of the stabilizer 100 in the process of increasing the voltage due to the resonance may not be applied to the LED light source array 700, as will be described later in the description of the subsequent load voltage determination unit 400. This is because the load switch 470 included in the load voltage determination unit 400 is in the off state.

Meanwhile, OCP (Over Current Protection) elements 210a and 210b, which are a type of fuse, may be disposed at both ends of the first switch 230. [ The OCP elements 210a and 210b may function to cut off an overcurrent during a voltage raising process or an overcurrent applied to a load after being turned on. In some cases, the OCP elements 210a and 210b may be omitted.

The rectifying unit 300 may include two bridge diodes 310 and 330 connected to an output terminal of the preliminary voltage driving unit 200. The rectifying unit 300 may rectify the AC voltage output from the preliminary voltage driving unit 200 to a DC voltage. The principle of rectification by the bridge diodes 310 and 330 is already known, and a description thereof will be omitted. The output terminal of the preliminary voltage driver 200 may be the same as the output terminal of the ballast 100. In this case, Therefore, it can be said that the rectifying unit 300 rectifies the AC voltage output from the ballast 100 to a DC voltage.

The load voltage determination unit 400 includes a smoothing capacitor 410, voltage measurement resistors 430a and 430b and an Over Voltage Protection (OVP) device 450, a load switch 470, and a buffer capacitor 490 .

The smoothing capacitor 410 smoothes the pulsating current of the rectifying unit 300 so that the voltage measuring resistors 430a and 430b can perform the voltage measurement stably and accurately. The voltage measuring resistors 430a and 430b may include a first voltage measuring resistor 430a and a second voltage measuring resistor 430b connected in series. The output voltage from the ballast 100 can be sensed by measuring the voltage between the terminals between the first and second voltage measurement resistors 430a and 430b based on the partial voltage principle by the series connection of the resistors.

The OVP device 450 can function to protect the circuit from overvoltage or surge voltage.

The load switch 470 is turned on when the output voltage of the ballast 100 reaches a predetermined preliminary voltage so that the output voltage of the load voltage determining unit 400 is applied to the LED light source array 700 . The load switch 470 can keep the off state as a default. Therefore, the output voltage of the load voltage determining unit 400 may not be applied to the LED light source array 700 in the process of raising the voltage by the resonance in the first ballast 100. [ The load switch 470 may be implemented through various devices that perform the switching function, such as the first and second input switches 230 and 250 described above.

As can be seen from the circuit, the output voltage of the load voltage determination unit 400 is also applied to the voltage / current regulator 600 as the load switch 470 is turned on. For reference, assuming that there is no voltage drop in the rectifier 300, the output voltage of the load voltage determiner 400 and the output voltage of the ballast 100 may be the same. Therefore, it may be said that as the load switch 470 is turned on, the output voltage of the ballast 100 is applied to the LED light source array 700. [

The buffer capacitor 490 is applied directly to the LED light source array 700 when the load switch 470 is turned on and the output voltage of the ballast, e.g., a high voltage, is applied directly to the LED light sources < 711 can be prevented from being destroyed.

Meanwhile, an AC / DC buck converter 500 may be connected to the output terminal of the load voltage determining unit 400. The AC / DC buck converter 500 can generate the DC down voltage by lowering the output voltage of the load voltage determiner 400, that is, the output voltage of the ballast 100. The DC down voltage may be DC 12V, for example. Of course, the value of the DC down voltage is not limited to 12V. The DC down voltage may be used to drive the switches arranged in the compatible drive circuit. For example, the first and second input switches 230 and 250, the load switch 470, and the serial parallel switches 751 and 753 in the LED light source array 700 can be used. The AC / DC buck converter 500 may be omitted if a separate power source is supplied for driving the switches.

The voltage and current regulator 600 is connected between the output terminal of the load voltage determining unit 400 and the output terminal of the LED light source array 700 to control the voltage and current applied to the LED light source array 700. The output terminal of the load voltage determination unit 400 may coincide with the output terminal of the ballast 100 and may also coincide with the input terminal of the LED light source array 700. Therefore, the voltage-current regulator 600 may be connected between the input and output terminals of the LED light source array 700.

More specifically, the voltage and current regulator 600 may include a first resistor 610a, a second resistor 610b, a FET (Feild Effect Transistor) 630, and a third resistor 680. The output terminal of the LED light source array 700 is connected to the drain of the FET 630 and the terminal between the first resistor 610a and the second resistor 610b is connected to the gate of the FET 630, The third resistor 680 may be connected to the source of the second resistor 630. [

The first resistor 610a and the second resistor 610b may be connected in series to each other and may be connected between the output terminal of the load voltage determining unit 400 and the third resistor 680. In addition, a terminal between the first resistor 610a and the second resistor 610b may be connected to the gate of the FET 630. [

The voltage at the terminal between the first resistor 610a and the second resistor 610b is determined by the output voltage of the load voltage determiner 400 based on the partial voltage principle by the series connection of the resistors, It may correspond to the partial voltage of the voltage. The first resistor 610a and the second resistor 610b may be a kind of voltage measuring resistor. Since the voltage at the terminal between the first resistor 610a and the second resistor 610b is input to the gate of the FET 630, the voltage at the terminal between the first resistor 610a and the second resistor 610b Accordingly, on-off of the FET 630 can be determined.

For example, when the voltage at the terminal between the first resistor 610a and the second resistor 610b, that is, the gate voltage of the FET 630 is smaller than the threshold voltage of the FET 630, the FET 630 is turned off, So that current can not flow through the LED light source array 700. [ When the voltage at the terminal between the first resistor 610a and the second resistor 610b becomes equal to or higher than the threshold voltage of the FET 630, the FET 630 is turned on, .

In other words, even if the output voltage of the ballast 100 is applied to the LED light source array 700, the LED light sources 711 in the LED light source array 700 may not be turned on since the FET 630 is in the off state. The output voltage of the ballast 100 continues to rise and the voltage at the terminal between the first resistor 610a and the second resistor 610b rises as the output voltage of the ballast 100 rises, Are turned on, LED light sources in the LED light source array 700 can be turned on.

On the other hand, even after the LED light sources are turned on, the output voltage of the ballast 100 can continue to rise. However, the gate voltage of the FET 630 thereby rises and the current flowing through the FET 630 also increases together, so that an excessive voltage increase of the output voltage of the ballast 100 can be prevented.

On the other hand, a third resistor 680 is disposed at the source of the second resistor 610b and the FET 630, and a current flowing through the third resistor 680 can be sensed. The third resistor 680 may be a kind of current sensing resistor. The voltage current regulator 600 can adjust the current flowing into the LED light source array 700 by changing the connection relationship of the LED light sources in the LED light source array 700 based on the sensed current. For example, when the current flowing to the LED light source array 700 is larger than the reference, the LED light sources in the LED light source array 700 are changed from a parallel connection relationship to a serial connection relationship, . Conversely, when the current flowing to the LED light source array 700 is below the reference value, the LED light sources are changed from a serial connection relationship to a parallel connection relationship or a parallel connection relationship is maintained, thereby increasing a current flowing to the LED light source array 700 have.

The LED light source array 700 may include a plurality of LED light sources 711 as a load for a compatible driving circuit. The LED light sources 711 may be connected to each other through at least one of a serial connection and a parallel connection. For example, as shown in the figure, a plurality of first LED light source pairs 710-1, ..., 710-n each having three LED light sources 711 connected in parallel are serially connected to each other, A plurality of second LED light source pairs 730-1, ..., 730-n, to which the LED light sources 711 are connected in parallel, may be connected in series. The first LED light source pairs 710-1, ..., 710-n connected in series to one another are referred to as a first LED light source group, and the second LED light source pairs 730-1, ..., 730- And 730-n are referred to as a second LED light source group, the first LED light source group and the second LED light source group may be connected in series or in parallel to each other through serial parallel switches 751 and 753. The serial parallel switches 751 and 753 may be implemented through various devices that perform the switching functions as the first and second input switches 230 and 250 described above.

The serial connection and the parallel connection of the first LED light source group and the second LED light source group will be described in more detail with reference to FIGS. 4A and 4B.

On the other hand, the connection relationship of the LED light sources 711 shown is only one example. Thus, in the LED light source array 700, the LED light sources 711 can be connected to each other with various serial and / or parallel connection structures different from the connection relationship illustrated in FIG. Also, by including at least two switches in the LED light source array 700, the connection relationship of the LED light sources 711 can be converted through the switches.

The LED fluorescent lamp 1000 including the compatible driving circuit of the present embodiment controls the output voltage of the ballast 100 to rise up to a predetermined preliminary voltage through the preliminary voltage driver 200, To the LED light source array 700 after the output voltage of the ballast 100 reaches the preliminary voltage. Meanwhile, the voltage applied to the LED light source array 700 can be controlled through the voltage and current regulator 600, and the connection relationship of the LED light sources in the LED light source array 700 can be converted into serial or parallel connection . Accordingly, the LED fluorescent lamp 1000 including the compatible driving circuit according to the present embodiment can stably light the LED light sources and keep the lighting stable, appropriately corresponding to the characteristics of various existing ballasts.

FIG. 3 is a flow chart showing an operation procedure of the electric / magnetic ballast compatible driving circuit in the LED fluorescent lamp of FIG. 2; For convenience of explanation, the circuit diagram of the LED fluorescent lamp of Fig. 2 is also referred to

Referring to FIG. 3, an initial voltage of the ballast 100 is applied to the preliminary voltage driver 200 (S111). The initial voltage can be applied in the form of AC power.

Next, when the initial voltage of the ballast 100 is applied, the input switches 230 and 250 in the preliminary voltage driver 200 are kept on (S113). As described above, since the input switches 230 and 250 keep the ON state as a default, there may be no other change.

Thereafter, the output voltage of the ballast 100 rises (S115). The rise of the output voltage of the stabilizer 100 can be achieved by generating resonance through the connection of the inductor 110 and the capacitor 120 by the input switches 230 and 250.

It is determined whether the output voltage of the ballast 100 has reached a predetermined preliminary voltage (S117). The partial voltage is sensed using the voltage measuring resistors 430a and 430b of the load voltage determining unit 400 so that the preliminary voltage can be determined. When the preliminary voltage has been reached (Yes), the load switch 470 is turned on (S119). If the preliminary voltage is not reached (No), the output voltage rising step S115 The output voltage of the ballast 100 due to the resonance continues to rise. For reference, the load switch 470 keeps the off state as a default, so that the load switch 470 is initially in the off state and switches to the on state when the output voltage of the ballast 100 reaches the preliminary voltage.

After the switch 470 is turned on, the buffer capacitor 490 is charged (S121).

When the load switch 470 is turned on through the charging of the buffer capacitor 490, the output voltage of the ballast 100, for example, a preliminary voltage of high voltage, is directly applied to the LED light source array 700, 700 to prevent destruction of the LED light sources 711.

The output voltage of the ballast 100 is lowered by the AC / DC buck converter 500 to generate a stable DC down voltage (S123). The DC down voltage may be DC 12V, for example. Of course, the DC down voltage is not limited to DC 12V. The DC down voltage may be used to drive the input switches 230 and 750 and the series-parallel switches 751 and 753.

Next, the input switches 230 and 750 are turned off (S125). The switching of the input switches 230 and 750 to the off state utilizes the DC down voltage and the input switches 230 and 750 are turned off so that the output current pattern of the ballast 100 is preheated the same as the current pattern after the pre-heat process is as described above.

The output voltage of the ballast 100 continues to rise (S127). The output voltage of the ballast 100 may rise until it reaches the rated output of the ballast 100. The output voltage of the ballast 100 can be stabilized when it reaches the rated output of the ballast 100. [

It is determined whether the gate voltage of the FET 630 is equal to or higher than the threshold voltage Vth (S129). Whether the gate voltage of the FET 630 is equal to or higher than the threshold voltage is determined by applying the voltage of the terminal between the first and second resistors 610a and 610b connected in series to the gate of the FET 630, It can be judged according to whether or not. Since the voltage at the terminal between the first and second resistors 610a and 610b corresponds to the partial voltage of the output voltage of the ballast 100, the on / off state of the FET 630 is eventually adjusted to the output voltage of the ballast 100 You can depend on it.

The LED light sources 711 in the LED light source array 700 are lit up (S131) and the gate voltage of the FET 630 is lower than the threshold of the FET 630 When the voltage is lower than the voltage (No), the voltage returns to the voltage increasing step S127 of the ballast 100 and the output voltage of the ballast 100 continues to rise. The lighting of the LED light sources 711 may be performed by flowing an electric current through the FET 630 connected to the output terminal of the LED light source array 700.

After the LED light sources 711 are turned on, the gate voltage of the FET 630 continues to rise (S133). The rise of the gate voltage of the FET 630 may ultimately be based on the output voltage rise of the ballast 100. [ The output voltage of the ballast 100 may be increased until the rated output of the ballast 100 is reached as described above in the step S127 of raising the output voltage of the ballast 100. [

The current of the LED light source array 700 is increased (S135). The reason for the current increase of the LED light source array 700 is as follows. The gate voltage of the FET 630 increases and the current flowing through the source and drain of the FET 630 increases due to the characteristics of the FET 630. As a result, So that the current flowing through the semiconductor device increases. As described above, by controlling the current flowing through the LED light source array 700 through the FET 630, the output voltage of the ballast 100 can be prevented from rising excessively.

It is determined whether the output of the ballast 100 has reached the rated output (S137). When the output of the ballast 100 reaches the rated output (Yes), the voltage of the ballast 100 is stabilized and the output voltage of the ballast 100 can be maintained as it is (S139). If the output of the ballast 100 does not reach the rated output (No), the gate voltage of the FET 630 rises back to the step S133 of increasing the gate voltage of the FET 630. [ The rise of the gate voltage of the FET 630 corresponds to the rise of the output voltage of the ballast 100 as described above.

Then, it is determined whether the current of the LED light source array 700 is greater than a preset current value (S141). If the current of the LED light source array 700 is larger than the preset current value (Yes), the LED light sources in the LED light source array 700 are changed to the serial connection structure (S143). If the current of the LED light source array 700 is not greater than the predetermined current value (No), the connection relationship of the LED light sources in the LED light source array 700 is maintained in a parallel connection structure (S145). When the connection relationship of the LED light sources in the LED light source array 700 has a serial connection structure, the load impedance becomes large and the consumed current can be reduced. Conversely, the consumption current may increase when the connection relationship of the LED light sources has a parallel connection structure. Meanwhile, the default of the connection relationship of the LED light sources in the LED light source array 700 may be a parallel connection structure.

4A and 4B are circuit diagrams illustrating a structure in which the LED light sources 711 in the LED light source array 700 in the LED fluorescent lamp of FIG. 3 are connected in series with a structure in which the LED light sources 711 are connected in parallel via a serial parallel switch. FIG. FIG. 4B shows a structure in which the LED light sources 711 are connected in series. FIG.

Referring to FIG. 4A, a first LED light source group 710 and a second LED light source pair 730-1, ..., 710-n, each of which is made up of first LED light source pairs 710-1, ..., 710- And the second LED light source group 730 composed of the first serial parallel switch 753 and the second serial light source group 730-n are connected through the first serial parallel switch 751, The first LED light source group 710 and the second LED light source group 730 can be connected in a parallel connection structure by connecting the fourth terminal? And the fifth terminal?

4B, the second terminal (2) and the third terminal (3) are connected through the first serial parallel switch 751 and the second serial parallel switch 753 is turned off to connect the fourth terminal (4) The first LED light source group 710 and the second LED light source group 730 may be connected in a serial connection structure.

The connection relationship of the LED light sources 711 in Figs. 4A and 4B is only one example. For example, each of the first LED light source pairs 710-1, ..., 710-n or the second LED light source pairs 730-1, ..., 730-n may include two LED light sources 711 may be connected in parallel or four or more LED light sources 711 may be connected in parallel. In some cases, the LED light sources 711 may be configured as one LED light source 711.

Meanwhile, the LED light source array 700 may include three or more LED light source groups. In addition, the LED light source array 700 may include three or more serial parallel switches.

While the present invention has been described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. will be. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

The present invention relates to a voltage stabilizer and a control method thereof, and more particularly, to a voltage stabilizer for an inductor, The present invention relates to a voltage regulator and a method of controlling the same and a method of controlling the same in a voltage regulator and a voltage regulator. 730-FET, 700: LED light source array 711: LED light source 710, 730: LED light source group 710-1, ... 710-n: first LED light source pairs 730-1, -n: third LED light source pairs, 751, 753: serial parallel switch.

Claims (12)

A pre-voltage driver connected to the output terminal of the electronic or magnetic ballast and controlling the resonance of the inductance L and the capacitance C of the ballast;
A rectifier connected to the preliminary voltage driver and rectifying the AC voltage to a DC voltage using a bridge diode;
A load voltage determination unit connected to the rectification unit and configured to delay the connection of the load until the output of the rectification unit reaches a predetermined first voltage so that the output voltage of the stabilizer rises; And
And a voltage current regulator connected to an output terminal of the load voltage determination unit (or an input terminal of the load) and an output terminal of the load, the voltage and current being adjusted by the voltage and current applied to the load,
Wherein the load is an LED light source array including a plurality of LED light sources,
Wherein the voltage and current controller adjusts the voltage and current by changing the connection relationship of the LED light sources in the LED light source array from serial to parallel or from parallel to serial. The method according to claim 1,
The preliminary voltage driving unit includes an input switch connected to the ballast output terminal for connecting the inductor of the ballast to the capacitor,
Wherein the load voltage determination unit includes a load switch for connection of the load,
The input switch remains on until the first voltage is reached,
And when the first voltage is reached, the load switch is turned on to connect the load, and the input switch is turned off. The method according to claim 1,
The voltage current regulator includes a first resistor and a second resistor connected to an output terminal of the load voltage determination unit and connected in series to each other, a field effect transistor connected to an output terminal of the load, and a third resistor connected to the FET and,
An output terminal of the load is connected to a drain of the FET, a terminal between the first resistor and the second resistor is connected to the gate of the FET, and the third resistor is connected to the source of the FET and the second resistor ,
The gate voltage of the FET corresponds to the partial voltage of the output voltage of the ballast, and when the output voltage of the ballast rises and the gate voltage of the FET becomes equal to or higher than the threshold voltage of the FET, Flowing,
And a current flowing to the third resistor is sensed to control a current flowing in the load. delete The method according to claim 1,
The electric / magnetic ballast compatible driving circuit further includes an AC / DC buck converter connected to the output terminal of the load voltage determination unit,
The AC / DC buck converter generates a down voltage by lowering the output voltage of the load voltage determination unit, and the down voltage is applied to the operation of the switch included in the electromagnetism- Wherein the ballast is a ballast. An electronic or magnetic ballast that raises the voltage through resonance of inductance and capacitance and limits the output current;
A preliminary voltage driver connected to an output terminal of the ballast to control the resonance;
A rectifier connected to the preliminary voltage driver for rectifying an AC voltage to a DC voltage using a bridge diode;
A load voltage determination unit connected to the rectification unit and configured to delay the connection of the load until the output of the rectification unit reaches a predetermined first voltage so that the output voltage of the stabilizer rises;
A load connected to the load voltage determining unit and including a plurality of LED light sources; And
And a voltage current regulator connected to an output terminal of the load voltage determination unit (or an input terminal of the load) and an output terminal of the load, the voltage and current being adjusted by the voltage and current applied to the load,
Wherein the load is an LED light source array including a plurality of LED light sources,
Wherein the voltage current regulator adjusts the voltage and current by changing the connection relationship of the LED light sources in the LED light source array from serial to parallel or from parallel to serial. The method according to claim 6,
The preliminary voltage driving unit includes an input switch connected to the ballast output terminal for connecting the inductor of the ballast to the capacitor,
Wherein the load voltage determination unit includes a load switch for connection of the load,
The input switch remains on until the first voltage is reached,
And when the first voltage is reached, the load switch is turned on to connect the load, and the input switch is turned off. 8. The method of claim 7,
Wherein the load voltage determination unit includes two resistors connected in series between an output terminal of the rectification unit and the ground,
Wherein the LED fluorescent lamp senses the voltage of the terminal between the two resistors to determine whether the voltage reaches the first voltage. The method according to claim 6,
The voltage current regulator includes a first resistor and a second resistor connected to the output terminal of the load voltage determination unit and connected in series to each other, a FET connected to the output terminal of the load, and a third resistor connected to the FET,
An output terminal of the load is connected to a drain of the FET, a terminal between the first resistor and the second resistor is connected to the gate of the FET, and the third resistor is connected to the source of the FET and the second resistor ,
The gate voltage of the FET corresponds to the partial voltage of the output voltage of the ballast, and when the output voltage of the ballast rises and the gate voltage of the FET becomes equal to or higher than the threshold voltage of the FET, Flowing,
Wherein a current flowing to the third resistor is sensed to control a current flowing in the load. delete The method according to claim 6,
The preliminary voltage driving unit includes an input switch connected to the ballast output terminal for connecting the inductor of the ballast to the capacitor,
Wherein the load voltage determination unit includes a load switch for the load connection,
The load comprising at least two serial parallel switches for changing the connection between the LED light sources from a serial connection to a parallel connection or changing from a parallel connection to a serial connection,
The LED fluorescent lamp further includes an AC / DC buck converter connected to an output terminal of the load voltage determination unit,
Wherein the AC / DC buck converter generates a DC down voltage by lowering the output voltage of the load voltage determining unit, and the DC down voltage is used to drive the input switch, the load switch, and the serial parallel switch. 12. The method of claim 11,
The input switch, the load switch, and the serial /
At least one transistor of a BJT (Bipolar Junction Transistor), a UJT (UniJunction Transistor), a PUT (Programmable Unijunction Transistor), a JPET (junction field effect transistor), a MOSFET (Metal Oxide Semiconductor FET), and an IGBT (Insulated Gate Bipolar Transistor)
A thyristor of at least one of a silicon controlled rectifier (SCR), a triac (TRIAC), and a gate turn off (GTO)
And the LED fluorescent lamp is implemented as a relay.

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