KR102344319B1 - A Driver Circuit for LED Lamp and a LED Lamp - Google Patents

Abstract

The present invention provides a driving circuit for an LED lamp having an afterglow prevention function and various protection functions, which has an extremely simple structure and minimized costs, and a driving circuit for an LED lamp having an afterglow prevention function and a protection function includes: a power supply and filter unit (100); a rectifying and smoothing unit (200) that rectifies and smooths AC power; an LED driving unit (300) that adjusts a current of rectified and smoothed DC power to drive an LED array; and an output unit (400) that stably outputs the DC power adjusted by the LED driving unit to the LED array, wherein the LED driving unit (300) includes a driving driver (310) that mainly performs constant current control as an internal on-chip PFC circuit, a driver driving voltage applying unit (320) that applies a driving voltage to the driving driver, an inductance unit (340) that smooths a voltage rectified and smoothed by the driving driver, and a feedback unit (330) that senses a voltage or a current of the inductance unit and feeds the voltage or the current back into the driving driver, the rectifying and smoothing unit (200) includes a bridge diode (BD1) for full-wave rectification and a second capacitor (CX2) for smoothing to remove a ripple of the rectified voltage, and a first capacitor (CX1) for an afterglow prevention function is connected in parallel with a variable resistor (RV1) to the power supply and filter unit (100) on a front end of the rectifying and smoothing unit (200) by reliably removing a residual voltage provided by the second capacitor (CX2) in a switched-off state.

Description

A driving circuit for an LED lamp having an afterglow prevention function and a protection function and a luminaire employing the same {A Driver Circuit for LED Lamp and a LED Lamp}

The present invention relates to a driving circuit for an LED lamp and a luminaire, and more particularly, an LED luminaire that prevents an afterglow phenomenon in which the LED is lit with a fine brightness even when the DC current of a set voltage supplied to the LED is cut off by operation of a lighting switch. It relates to a driving circuit and a luminaire for LED lamps having an afterglow prevention function and various protection functions.

In general, as a luminaire installed on the ceiling or wall of a room, the current consumption is very low compared to the fluorescent lamp, the lifespan is semi-permanent, and a luminaire using an LED (Light Emitting Diode) lamp that can emit light close to natural light is mainly used. In recent years, the supply of luminaires including such LEDs has been more actively made to save power.

Since the LED having such an advantage is lit by receiving a direct current of a set voltage due to its characteristics, a power supply device (Switching Mode Power Supply, SMPS) to convert and supply AC current to DC current of the set voltage to light the LED.

And, as shown in FIG. 1 , the LED lighting fixture 1 ′ has a neutral terminal (N) and a voltage terminal (S) of the main power supply unit 10 through a first lead wire (L1) and a second lead wire (L2). a DC converter 20 for rectifying and converting the AC current supplied from the DC current to a DC current of a set voltage; an LED lighting unit 30 having one or more LEDs for receiving a direct current of a set voltage output from the direct current conversion unit 20 to light; and a lighting switch (SW) for controlling the connection state of the first lead wire (L).

On the other hand, when the first lead wire is connected by the lighting switch and the circuit is connected, the AC current input through the neutral terminal and the voltage terminal is converted into a DC current of the set voltage through the DC converter and input to the LED lighting part where the LEDs are arranged. Thus, the LED is turned on, and when the first lead wire is disconnected by the lighting switch, the circuit is disconnected and the LED is turned off.

However, since the LED luminaire is installed in close contact with the ceiling or wall surface of the building forming the grounding part due to its characteristics, even if the first lead wire is blocked by the lighting switch, the second lead wire is connected to the ceiling of the building through the voltage terminal. A so-called afterglow phenomenon in which an induced electromotive force (Ie), which is a microcurrent, is induced between the ground parts (G), and the LED constituting the LED lighting unit (30) is lit with low illuminance by the induced electromotive force (Ie). This inevitably happens.

As such, when the afterglow phenomenon in which the LED constituting the LED lighting unit is turned on at low illuminance occurs, current is continuously consumed by the induced electromotive force, so unnecessary current consumption occurs, and the lifespan of each component constituting the LED lighting circuit is shortened. On the other hand, it is difficult to get a good night's sleep or rest, so users complain about the afterglow phenomenon.

In order to solve the above problems, Korean Patent No. 10-1684384 (an afterglow prevention circuit of an LED lighting luminaire and an LED lighting luminaire configured including the same) has been proposed as the first prior art. It is a block diagram showing an LED lighting/LED luminaire equipped with an afterglow prevention circuit according to the present invention.

The first LED lighting / LED lighting fixture 1 according to the prior art, as shown in FIG. 1, the neutral terminal (N) of the main power supply unit 10 through the first lead wire (L1) and the second lead wire (L2) and a DC converter 20 for rectifying and converting an AC current supplied from any one of the voltage terminals R, S, and T into a DC current of a set voltage; an LED lighting unit 30 having one or more LEDs for receiving a direct current of a set voltage output from the direct current conversion unit 20 to light; and a lighting switch (SW) for switching the first lead wire, wherein the LEDs are disposed in series or in parallel on the substrate 31 to form the LED lighting unit 30, the first lead wire (L1) and the second Any one of the two lead wires (L2) (L1) is normally connected to the neutral terminal (N), and the other lead wire (L2) is connected to the voltage terminal (S) of any one of the voltage terminals (R, S, T). It is connected to receive an alternating current from the neutral terminal (N) and any one voltage terminal (S).

And, the DC converter 20 that rectifies the AC current and converts it into a DC current of a set voltage is composed of a bridge rectifying device BD, and is supplied through the first lead wire L1 and the second lead wire L2. It converts the current by rectifying it into direct current.

In addition, a smoothing capacitor C1 for smoothing the DC current through the storage and discharging of the rectified and converted DC current is disposed in the DC converter 20, and the DC current is stored and discharged by the smoothing capacitor C1. A DC current of a smoothed set voltage is continuously supplied to the LED lighting unit 30 .

That is, the smoothing capacitor C1 smoothes the DC current whose voltage is increased or decreased by the frequency through the power storage and discharge action, and the DC current of the set voltage is continuously supplied to the LED lighting unit 30 to flicker the lit LED. Make sure to keep the light on continuously.

Therefore, when the circuit is connected with the first lead wire L1 disconnected by the lighting switch SW, the AC current input through the neutral terminal N and any one of the voltage terminals R, S, T is While passing through the DC converter 20, it is rectified and converted into a DC current of a set voltage, and is input to the LED lighting unit 30 in which the LEDs are arranged to light up each LED.

And, when the first lead wire L1 is disconnected through the lighting switch SW, the circuit formed between the neutral terminal N and any one of the voltage terminals R, S, T is disconnected, and the LED is turned off do.

Thus, in implementing this LED lighting / LED lighting fixture (1), the voltage terminal (S) and the ground portion (G) of the ceiling light of the building in a state in which the first lead wire (L1) is disconnected by the lighting switch (SW) By blocking the induced electromotive force (Ie), which is a microcurrent of the voltage induced in between, from flowing along the LED lighting, the LED is turned on by the induced electromotive force, which is a microcurrent flowing between the voltage terminal (S) and the ground (G). The so-called afterglow phenomenon in which the LED of the unit 30 is turned on at low illuminance is prevented.

To this end, in the first prior art, an afterglow prevention circuit 40 is disposed between the DC conversion unit 20 and the LED lighting unit 30, and between the voltage terminal S and the ground unit G when the light is turned off. The so-called afterglow phenomenon in which each LED of the LED lighting unit 30 is turned on at low illuminance by the induced electromotive force, which is a microcurrent flowing along the , is prevented.

The afterglow prevention circuit 40 includes one or more resistance elements R1 and R2 for reducing the DC current of the set voltage supplied from the DC converter 20 to a switching voltage, and an LED lighting unit disconnected by the switching voltage. It is configured to include an SCR switch (Q1) for connecting the circuit section between the 30 and the DC converter (20).

And, in the first prior art, a capacitor element (C2) for delaying the switching voltage supplied to the SCR switch (Q1) after being reduced in pressure by the resistance elements (R1, R2) is disposed in the afterglow prevention circuit (40), By temporarily delaying the switching voltage by the capacitor element C2 and then supplying it to the SCR switch Q1, the SCR switch Q1 is protected by the initial switching voltage.

Therefore, when the first lead wire L1 is connected by the lighting switch SW and AC current is supplied from the main power supply unit 10 to the DC conversion unit 20, the afterglow prevention circuit 40 is disconnected DC conversion The DC current provided by the unit 20 is connected between the DC converter 20 and the LED lighting unit 30 .

That is, the DC converter 20 rectifies the AC current into a DC current of a set voltage and converts the DC current of the set voltage to a switching voltage by the resistance elements R1 and R2 constituting the afterglow prevention circuit 40 . , and the SCR switch Q1 detects the reduced switching voltage and connects the disconnected LED lighting unit 30 and the DC converter 20 .

Thus, when the user connects the first lead wire L1 through the lighting switch SW, the LEDs constituting the LED lighting unit 30 are supplied with a DC current of a set voltage and are stably turned on.

Then, when the first lead wire L1 is disconnected by the lighting switch SW and the supply of AC current to the DC converter 20 is cut off, the DC current of the set voltage stored in the smoothing capacitor C1 is consumed by the LED. When the LED lighting unit 30 is turned off, at the same time, the SCR switch Q1 of the afterglow prevention circuit 40 disconnects between the DC converter 20 and the LED lighting unit 30 .

Thus, the LED lighting/LED lighting fixture 1 configured including the afterglow prevention circuit according to the first prior art is disconnected between the DC converter 20 and the LED lighting part 30 by the afterglow prevention circuit when the lights are turned off. As a result, the induced electromotive force (Ie), which is a microcurrent between the LED lighting and the ground, is induced and supplied to the LED lighting unit 30, so that the afterglow phenomenon in which the LED is turned on with low brightness can be prevented.

In addition, in the first prior art, a diode D1 for preventing reverse flow is disposed between the DC converter 20 and the LED lighting unit 30 .

With this configuration, the afterglow phenomenon in which the LED of the LED lighting unit 30 is finely lit while the induced electromotive force, which is a microcurrent induced electromotive force, circulates through the LED lighting unit 30 and the DC converter 20 in forward and reverse directions is prevented. .

However, in the first prior art, since a semiconductor device such as a thyristor or FET is used, there is a problem that the efficiency of the lighting device is lowered due to the high price and the added parts.

In order to solve the problems of the first prior art, Korean Patent No. 2052116 (afterglow removal and surge improvement circuit of an alternating current light emitting diode lighting device) has been newly proposed as the second prior art.

That is, the prior art effectively removes the afterglow caused by the leakage current by suppressing the leakage current generated in the light emitting diode lighting device driven by the second alternating current from being transmitted to the light emitting diode, while effectively reducing the performance due to the surge. 2, a DC power supply unit 2100, a light emitting diode unit 2300, a current control unit 2220, a leakage current suppressor 2510, a surge induction unit 2520, a surge protection unit ( 2400 ), a driving detection unit 2210 , and a switching unit 2530 may be included.

The DC power supply unit 2100 receives AC power to provide DC power, and the light emitting diode unit 2300 is driven by DC power delivered by the DC power supply unit 2100 and is composed of a plurality of light emitting diodes, and a current control unit. Reference numeral 2220 controls the current flowing through the plurality of light emitting diodes of the light emitting diode unit 2300 .

On the other hand, the leakage current suppressor 2510 is disposed between the current control unit 2220 and the light emitting diode unit 2300, the leakage current generated by the DC power supply unit 2100 or the current control unit 2220 is the Transmission to the light emitting diode unit 2300 is suppressed.

Specifically, as shown in FIG. 2 , the leakage current suppressor 2510 includes a first diode D1 having an anode connected to the current controller 2220 and a cathode connected to the light emitting diode unit 2300 .

In addition, the surge inducing unit 2520 induces a surge incoming from the outside to bypass the light emitting diode unit 2300 .

Here, the surge inducing unit 2520 is composed of a plurality of diodes, and specifically, the surge inducing unit 2520 is a second diode D2 disposed in the opposite direction to a portion of the light emitting diodes of the light emitting diode unit 2300 . and a third diode D3 disposed in a direction opposite to that of the other light emitting diodes of the light emitting diode unit 2300 .

On the other hand, the surge protection unit 2400 transmits the surge induced by the surge induction unit 2520, and specifically, is composed of a TVS (Transient Voltage Suppressor), a varistor or a capacitor.

In addition, the driving detection unit 2210 detects whether the current control unit 2220 drives the light emitting diode unit 2300 , and the switching unit 2530 is composed of a transistor TR1 as shown in FIG. 2 , and the When the current control unit 2220 drives the light emitting diode unit 2300 by the driving detection unit 2210 , the surge protection unit 2400 is enabled.

However, the second prior art also requires several semiconductor elements, and additional devices including a switching element must be added.

Moreover, both of the first and second prior arts were insufficient in protection against various abnormal conditions such as overvoltage or other LED light-emitting units short-circuited or opened.

Republic of Korea Patent No. 1684384 (Afterglow prevention circuit of LED lighting luminaire and LED lighting luminaire comprising the same) Republic of Korea Patent No. 2052116 (Afterglow removal and surge improvement circuit of AC light emitting diode lighting equipment)

The present invention, as a countermeasure against the problems of the first and second prior art, is a driving circuit and a luminaire for an LED lamp having an afterglow prevention function and various protective functions. To provide a driving circuit and a luminaire for an LED lamp having a.

A driving circuit for an LED lamp having an afterglow prevention function and a protection function according to an aspect of the present invention for achieving the above object includes a power supply and filter unit 100 for receiving and filtering commercial AC power; a rectifying and smoothing unit 200 for rectifying and smoothing the AC power supplied by the power supply and filter unit; an LED driving unit 300 for driving an LED array (not shown) by controlling the current of the DC power source rectified and smoothed by the rectifying and smoothing unit; and an output unit 400 stably outputting the regulated DC power from the LED driving unit to the LED array; The LED driving unit 300 includes a driving driver 310 mainly performing constant current control as an internal on-chip PFC circuit, a driver driving voltage applying unit 320 applying a driving voltage to the driving driver, and the driving Consists of an inductance unit 340 for smoothing the voltage controlled by a constant current by a driver, and a feedback unit 330 for sensing the voltage or current of the inductance unit and feeding it back to the driving driver, and the rectification and smoothing unit 200 is composed of a bridge diode for full-wave rectification (BD1) and a second capacitor for smoothing (CX2) for removing a ripple of the rectified voltage, and the residual voltage provided by the second capacitor (CX2) in a switched-off state A first capacitor (CX1) for an afterglow prevention function by reliably removing The driving driver 310 is a BP2335 series IC chip, a driving driver IC (U1) and its peripheral circuit elements are used, and the driver driving voltage applying unit 320 is a startup connected to the VCC pin of the driving driver IC (U1). Consists of resistors R1 and R2 and a third capacitor CE1, and an upper power terminal P1 of the driver driving voltage applying unit 320 is connected to the second capacitor CX2 for smoothing and a lower power terminal P2 ) is a floating ground (GND) through the first diode D1, and the feedback unit 330 is connected to the input/output terminal of the inductance unit 340 to obtain the voltage and current of the output unit 400. It is sensed and fed back to the driving driver IC (U1) to achieve various circuit protection functions.

Preferably, the first capacitor (CX1) is a metallized film capacitor, characterized in that the capacity of the first capacitor (CX1) is in the same order as that of the second capacitor (CX2).

More preferably, the first and second capacitors CX1 and CX2 are all metallized film capacitors, and the capacitance of the first capacitor CX1 is three times or more than that of the second capacitor CX2. It is characterized by a large capacity.

delete

More preferably, the CS pin of the driving driver IC U1 is connected to the input terminal P3 of the inductor T1 of the inductance unit 340, and when the inductor output is short-circuited or the inductor is saturated, the driving By turning off the power MOSFET inside the driver IC (U1), the entire system elements are protected, and the input terminal P3 of the inductor T1 is connected to the 'FB' pin terminal through the fourth resistor R4. When the output voltage (V+) is sensed at the FB pin by the third and fourth resistors R3 and R4 for voltage division, the sensed voltage value deviates from the preset overvoltage and falling threshold voltage thresholds. , the driving switching element inside the driving driver IC (U1) is turned off to protect the entire circuit.

Most preferably, the VCC pin terminal P4 of the driving driver IC U1 is connected to the upper power terminal of the output unit 400 through the eighth and ninth resistors R8 and R9 and the second diode D2. It is connected to (V+), and after the driving driver IC (U1) operates and the output voltage (V+) is established, the output voltage (V+) is fed back through the feedback unit 330 as a feedback, the feedback When the power supplied through the feedback through the unit 330 is insufficient, the operation of the driving driver IC (U1) is stopped, and when the error condition is removed, the system resumes normal operation.

According to another aspect of the present invention for achieving the above object, a driving circuit (1) for an LED lamp having the afterglow prevention function and a protection function, and a driving circuit (1) for an LED lamp having the afterglow prevention function and a protection function A novel luminaire comprising an LED lamp (2) driven by

According to the present invention, as a driving circuit for an extremely simple and minimally priced LED lamp, it is possible to provide an afterglow prevention function and various protective functions.

Other objects and advantages of the present invention in addition to the above objects and effects will become apparent through the detailed description of the embodiments with reference to the accompanying drawings.

1 is a block diagram showing an LED lighting/LED luminaire having an afterglow prevention circuit according to a first prior art.
2 is a circuit diagram of an afterglow removal and surge improvement circuit of an AC light emitting diode lighting device according to a second prior art;
3 is a circuit diagram of a driving circuit for an LED lamp having an afterglow prevention function and a protection function according to the present invention.
4 and 5 are a PCB photograph of a driving circuit for an LED lamp having an afterglow prevention function and a protection function according to the present invention.
6 is a layout view of various elements of a driving circuit for an LED lamp having an afterglow prevention function and a protection function according to the present invention.
7 is a luminaire including a driving circuit (1) for an LED lamp having an afterglow prevention function and a protection function according to the present invention and the LED lamp (2).
8 is a photograph of a turn-on state of a luminaire including a driving circuit (1) for an LED lamp having an afterglow prevention function and a protection function according to the present invention and the LED lamp (2).
9 is a photograph of a turn-off state of a luminaire including a driving circuit (1) for an LED lamp having an afterglow prevention function and a protection function according to the present invention and the LED lamp (2).

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

(Drive circuit for LED lamp with afterglow prevention function and protection function)

First, a driving circuit 1 for an LED lamp having an afterglow prevention function and a protection function according to an optimal embodiment of the present invention will be described with reference to FIGS. 3 to 9 .

3 is a circuit diagram of a driving circuit for an LED lamp having an afterglow prevention function and a protection function according to the present invention, and FIGS. 4 and 5 are an upper side and a driving circuit for an LED lamp having an afterglow prevention function and a protection function according to the present invention It is a picture of the lower PCB, and FIG. 6 is a layout view of various elements of a driving circuit for an LED lamp having an afterglow prevention function and a protection function according to the present invention.

7 is a schematic view of a luminaire including a driving circuit 1 and an LED lamp 2 for an LED lamp having an afterglow prevention function and a protection function according to the present invention, and FIG. 8 is an afterglow prevention function and a protection function according to the present invention It is a photograph of a turn-on state of a luminaire including a driving circuit for an LED lamp (1) and an LED lamp (2) having And it is a picture of the turn-off state of the luminaire including the LED lamp (2).

A driving circuit for an LED lamp having an afterglow prevention function and a protection function of an optimal embodiment of the present invention, as shown in FIG. 3, includes a power supply and filter unit 100 for filtering and receiving commercial AC power; a rectifying and smoothing unit 200 for rectifying and smoothing the AC power supplied by the power supply and filter unit; an LED driving unit 300 for driving an LED array (not shown) by controlling the current of the DC power source rectified and smoothed by the rectifying and smoothing unit; and an output unit 400 stably outputting the regulated DC power from the LED driving unit to the LED array; is composed of

At this time, the LED driving unit 300 includes a driving driver 310 mainly performing constant current control as an internal on-chip PFC circuit, a driver driving voltage applying unit 320 applying a driving voltage to the driving driver, and to the driving driver. It consists of an inductance unit 340 for smoothing the voltage controlled by the constant current, and a feedback unit 330 which senses the voltage or current of the inductance unit and feeds it back to the driving driver.

In particular, the rectifying and smoothing unit 200 includes a bridge diode BD1 for full-wave rectification and a second capacitor CX2 for smoothing for removing a ripple of the rectified voltage, and in a switched-off state, the second A first capacitor (CX1) for an afterglow prevention function by reliably removing the residual voltage provided by the capacitor (CX2) is a variable resistor ( RV1) and connected in parallel.

Preferably, as the first and second capacitors CX1 and CX2, a metallized film capacitor is used, and more preferably, a metal-deposited polypropylene capacitor having a capacity of several μF to (several/10) μF is used. . That is, it is preferable that the capacity of the first capacitor CX1 is in the same order as that of the second capacitor CX2. For example, when the rated power of the LED lamp is 220V, 60Hz, and 10W, the capacity of the second capacitor CX2 is preferably about 0.15 μF, and the capacity of the second capacitor CX2 is most preferably about 0.71 μF. Bar, it is preferable that the capacitance of the first capacitor CX1 is three times or more greater than the capacitance of the second capacitor CX2.

The LED driving unit 300 will be described in more detail with reference to FIGS. 3 to 6 . As the driving driver 310, for example, the BP2335 series IC chip U1 and its peripheral circuit elements may be used. For reference, the BP2335 series of IC chips is a high-precision non-isolated buck driver with active power factor correction (PFC), especially for high mains input offline constant current LED lighting. Achieving low THD, with few external components, the LED output current can be precisely controlled.

In detail with respect to the driver driving voltage applying unit 320 of the LED driving unit 300, it consists of start-up resistors R1 and R2 and a third capacitor CE1 connected to the VCC pin of the driving driver 310. , when the system power is turned on by the switching SW1, the third capacitor CE1 is charged by the start-up resistors R1 and R2, and when the charging voltage reaches a predetermined turn-on threshold, the driving driver IC ( The internal circuit of U1) starts to work. For reference, the upper power terminal P1 of the driver driving voltage applying unit 320 is connected to the second capacitor CX2 for smoothing, and the lower power terminal P2 is connected to the floating ground GND through the first diode D1. ) has been

On the other hand, the COMP pin of the driver IC (U1) is connected to the floating ground (GND) through the second capacitor for loop compensation, and the COMP pin voltage is quickly pulled up to, for example, 5V, and then the system Initially, switching is started at a frequency of 10 kHz, for example. And in response, the COMP pin voltage rises gradually, and eventually the peak current of the inductor T1 also rises, so that the LED current achieves a soft start without overshooting.

In addition, the feedback unit 330 of the present invention senses the voltage and current of the output unit, and is fed back to the driving driver IC (U1), thereby achieving various circuit protection functions.

First, the CS pin of the driving driver IC (U1) is connected to the input terminal P3 of the inductor T1 of the inductor unit 340. The current of the inductor T1 is the inductor T1. is sensed during the entire switching cycle at the input-side terminal (P3) of That is, when the inductor output is short-circuited or the inductor is saturated, the CS peak voltage becomes relatively high, and when the CS voltage reaches an internal limit (1.5V for example), the power MOSFET inside the chip is immediately turned off, thereby shutting down the entire system components. will protect

Similar to the current sensing of the inductor T1, the input terminal P3 of the inductor T1 is connected to the 'FB' pin terminal through the fourth resistor R4, and the FB pin is the output voltage (V+) ) is used to sense by the third and fourth resistors R3 and R4 for voltage division, the threshold voltage for overvoltage is set to, for example, 1.6V, and the FB falling threshold voltage is, for example, 0.15V hysteresis. It can be set to 0.2V with Thus, when (R4/(R3+R4))*(V+), which is the divided voltage value of the output voltage (V+) sensed at the FB pin, deviates from the threshold, driving the inside of the driver IC (U1) By turning off the switching element, the entire circuit is protected.

In addition, once the driving driver IC U1 operates and the output voltage V+ is established, the VCC pin terminal P4 of the driving driver IC U1 is connected to the eighth and ninth resistors R8 and R9. ) and the second diode D2, it is connected to the upper power terminal (V+) of the output unit 400, and the VCC power is fed back by the output voltage (V+). , the operation of the driving driver IC (U1) is stopped.

For example, when the LED array is open circuit, the output voltage (V+) gradually rises. The output voltage is sensed by the FB pin when the power MOSFET inside the chip is turned off. The fault logic is triggered and the system stops switching.

Conversely, when the LED array is short-circuited, the switching frequency is operated below 7 kHz, for example, the output voltage (V+) is lowered and the VCC pin cannot be charged with the output voltage (V+) through the feedback unit, so the VCC pin voltage gradually decreases until it finally reaches the polling threshold. After the system enters a fault state, the VCC voltage decreases until it reaches a polling threshold, which restarts the system again.

Of course, once the fault condition is removed, the system will resume normal operation, and when the output is shorted or the inductor saturates, the CS peak voltage becomes relatively high, causing the CS voltage to reach its internal limit (1.5V for example), as described above. Then, the power MOSFET inside the chip is immediately turned off, protecting the entire system components.

(a driving circuit for LED lamps with afterglow prevention and protection functions and luminaires including LED lamps)

Hereinafter, a luminaire including a driving circuit 1 for an LED lamp and an LED lamp 2 having an afterglow prevention function and a protection function according to an optimal embodiment of the present invention will be described with reference to FIG. 7 .

7 is an actual photograph of a luminaire including the LED lamp driving circuit 1 and the LED lamp 2 having an afterglow prevention function and a protection function according to the present invention.

In addition, as shown in the photo of the turn-on/turn-off state of the luminaire including the LED lamp driving circuit 1 and the LED lamp 2 having an afterglow prevention function and a protection function according to the present invention, the turn-on state (FIG. 8) reference), in the turn-off state (refer to FIG. 9), it can be confirmed that the afterglow disappears immediately after being turned off.

In the above, the present invention has been described according to an embodiment of the present invention, but changes and modifications made by those of ordinary skill in the art to which the present invention pertains without departing from the technical spirit of the present invention also belong to the present invention. Of course.

1: Driving circuit for LED lamp
2: LED lamp
100: power supply and filter unit
200: rectification and smoothing part
300: LED driving unit 310: driving driver
320: driver driving voltage applying unit 330: feedback unit
340: inductance unit
400: output unit

Claims (7)

a power supply and filter unit 100 that receives and filters commercial AC power;
a rectifying and smoothing unit 200 for rectifying and smoothing the AC power supplied by the power supply and filter unit;
an LED driving unit 300 for driving the LED array by controlling the current of the DC power rectified and smoothed by the rectifying and smoothing unit; and
an output unit 400 stably outputting the regulated DC power from the LED driving unit to the LED array;
includes,
The LED driving unit 300 includes a driving driver 310 for performing constant current control as an internal on-chip PFC circuit, a driver driving voltage applying unit 320 for applying a driving voltage to the driving driver, and constant current control by the driving driver. Consists of an inductance unit 340 for smoothing the resulting voltage, and a feedback unit 330 sensing the voltage or current of the inductance unit and feeding it back to the driving driver,
The rectification and smoothing unit 200 includes a bridge diode BD1 for full-wave rectification and a second capacitor CX2 for smoothing for removing a ripple of the rectified voltage, and in a switched-off state, the second capacitor ( A first capacitor (CX1) for an afterglow prevention function by reliably removing the residual voltage provided by CX2) is supplied to the power supply and filter unit 100 of the front stage of the rectification and smoothing unit 200, and a variable resistor (RV1) connected in parallel with
The driving driver 310 is a BP2335 series IC chip driving driver IC (U1) and its peripheral circuit elements are used,
The driver driving voltage applying unit 320 includes start-up resistors R1 and R2 connected to the VCC pin of the driving driver IC U1 and a third capacitor CE1, and the driver driving voltage applying unit 320 ), the upper power terminal (P1) is the second capacitor (CX2) for smoothing, and the lower power terminal (P2) is a floating ground (GND) through the first diode (D1),
The feedback unit 330 is connected to the input/output terminal of the inductance unit 340, senses the voltage and current of the output unit 400, and is fed back to the driving driver IC (U1), thereby protecting various circuits. A driving circuit for an LED lamp having an afterglow prevention function and a protection function, characterized in that it achieves. The method of claim 1,
The first capacitor (CX1), a metallized film capacitor is used,
A driving circuit for an LED lamp having an afterglow prevention function and a protection function, characterized in that the capacity of the first capacitor (CX1) is in the same order as that of the second capacitor (CX2). 3. The method of claim 2,
The first and second capacitors (CX1, CX2) are all metallized film capacitors, and the capacitance of the first capacitor (CX1) is three or more times larger than that of the second capacitor (CX2). A driving circuit for LED lamps with afterglow prevention and protection functions. delete The method of claim 1,
When the CS pin of the driving driver IC U1 is connected to the input terminal P3 of the inductor T1 of the inductance unit 340 and the inductor output is short-circuited or the inductor is saturated, the driving driver IC U1 By turning off the internal power MOSFET, the entire system elements are protected,
The input terminal P3 of the inductor T1 is connected to the 'FB' pin terminal through the fourth resistor R4, so that the output voltage V+ at the FB pin is divided by third and fourth resistors R3, R4), and when the sensed voltage value deviates from the preset overvoltage and falling threshold voltage thresholds, the driving switching element inside the driving driver IC U1 is turned off to protect the entire circuit A driving circuit for an LED lamp having an afterglow prevention function and a protection function, characterized in that it is The method of claim 1,
The VCC pin terminal P4 of the driving driver IC U1 is connected to the upper power terminal V+ of the output unit 400 through the eighth and ninth resistors R8 and R9 and the second diode D2. After the driving driver IC (U1) operates and the output voltage (V+) is established, the output voltage (V+) is fed back through the feedback unit (330), and the feedback unit (330) LED lamp with afterglow prevention function and protection function, characterized in that when the power supplied through the feedback is insufficient, the operation of the driving driver IC (U1) is stopped, and the system resumes normal operation when the error condition is removed driving circuit. A driving circuit (1) for an LED lamp having an afterglow prevention function and a protection function according to any one of claims 1 to 3, 5 and 6;
A luminaire comprising an LED lamp (2) driven by a driving circuit (1) for an LED lamp having the afterglow prevention function and protection function.

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