KR100916851B1 - Constant current type light emitting diode lighting circuit - Google Patents

Abstract

A constant current type LED lighting circuit is provided to prevent voltage resonance or current resonance by controlling a voltage and a current at the same time. A current detection control part(70) detects and controls a current flowing to an LED module(60) through a current monitor(71) and a first photocoupler(72). A voltage detection control part(80) detects and controls a voltage of both ends of the LED module through a second photocoupler(81). A calculation control part(90) controls a detection value of the current detection control part and the voltage detection control part at the same time. A detection current stabilizing part(100) includes an R25 resistor and an R15 resistor. The R25 resistor detects abnormality of a current. The R15 resistor delivers a detection value of the R25 resistor to a C13 condenser.

Description

Constant power type LED lighting circuit {CONSTANT CURRENT TYPE LIGHT EMITTING DIODE LIGHTING CIRCUIT}

The present invention relates to a constant-power LED lighting circuit, and more particularly, to improve the efficiency of the LED lighting circuit operating at 320V or more, and also to MOS (Metal Oxide Semicondcutor) field effect transistor (FET) and light emitting diode ( LED: This prevents the breakage of light emitting diodes and greatly improves the quality and reliability of the product, enabling consumers to plant good images.

As is well known, constant current means that constant current flows unconditionally regardless of load.

Light emitting diodes for display devices are generally driven at the constant current described above to reduce luminance fluctuations. In the case where the brightness of the light emitting diode is adjusted according to the use, the current setting of the constant current circuit is changed and adjusted, but the voltage drop of the light emitting diode changes greatly depending on the driving current. For this reason, the terminal voltage of the output transistor which comprises the output terminal of a constant current circuit changes large.

Since the constant current circuit uses the drain electrode of the MOS transistor as an output terminal, if the voltage of the output terminal is greatly changed, there is a problem in that the output current varies due to the channel length modulation effect of the MOS transistor, resulting in uneven brightness of the light emitting diode.

The light emitting diode (LED) may operate when a constant current is stably supplied to the current driving device. In particular, LEDs that require high power generate a lot of heat in the LEDs themselves because of their large driving current (typically 350mA or more), which results in a higher degradation rate of luminance than LEDs at low power. This is directly linked to the lifetime of the LED and is very important in the lighting market. Accordingly, all LEDs at high power are driven with a constant current, and are driven in a pulse width modulation (PWM) scheme to more efficiently use the power of the SMPS used as the constant current power source.

The LED-based lighting is actively developed worldwide due to various advantages such as high energy saving (80% compared to incandescent bulbs, 50% compared to fluorescent lamps), semi-permanent use (100 times longer than fluorescent lamps), and eco-friendly and emotional lighting characteristics. It's going on.

Conventionally, a driving circuit for supplying and driving power to an LED lighting device is mainly composed of SMPS (Switching Mode Power Supply) for supplying a constant voltage.

In the constant voltage type driving circuit (SMPS), the current is difficult to be constantly supplied to the entire LED module in which the LEDs are connected in series and parallel. Failure to control the LED causes problems such as LED failure and reduced lifespan.

In order to solve the heat problem, the LED lighting device that is supplied with a constant voltage and is illuminated with a large heat sink, or a temperature protection circuit is added to thoroughly manage the LED rank, has been a factor in raising the unit price.

In order to solve the above problems, a patent application No. 2008-0083435 (Registration No. 0877521) (name: LED lighting driving circuit) has been filed and registered.

That is, the above conventional technology is shown in Figure 1, the LED lighting driving circuit includes a rectifier for rectifying the input power; An inductor for charging current by the output power of the rectifier and discharging the charged current; A transistor for boosting or stepping down the output power of the rectifier by switching the current to charge or discharge the inductor; A smoothing unit for smoothing the power up or down by the transistor and supplying the power to the LED module; A feedback unit for sensing and feeding back the magnitude of the output power of the smoothing unit; A coil for detecting a zero point of the current flowing through the inductor; Receiving a signal fed back from the feedback unit so that the smoothing unit outputs an electrostatic source (constant voltage or constant current), and by receiving a zero point signal from the coil to compensate for the power factor of the rectifier output power, for switching of the transistor And a control unit for controlling a pulse width and a pulse frequency of a pulse waveform applied to the transistor, wherein the feedback unit detects a current flowing through the LED module, and a photo transmitting a current sensed by the detector. And a comparator and a comparator for comparing the current transmitted by the photocoupler with a reference current and transmitting the current to the controller, wherein the controller is configured to control the switching of the transistor according to a signal transmitted by the comparator. It characterized in that to output. Reference numeral 10 is a rectifier, 20 is a control unit, 30 is a gain compensation unit, 40 is a smoothing unit, 50 is a feedback unit, 51 is a sensing unit, 52 is a photocoupler, 60 is an LED module.

The conventional technology reduces the energy waste by boosting or stepping down the commercial AC power input and supplying power to the LED module by increasing the power factor and simultaneously supplying power to the LED module, thereby feeding back the current supplied to the LED module to continuously supply constant current to the LED module. The present invention relates to an LED lighting driving circuit capable of maintaining a constant brightness of the LED module lights, reducing the amount of heat generated, thereby improving efficiency and preventing the life of the LED module from being shortened.

However, the above-described conventional technology can be used only in 320V or less in structure, a big problem that can not be used in 450V or less at 320V or more.

In addition, the above-described conventional technology has a problem that the structural efficiency is low as 95% or less, a big problem in use occurs.

In addition, the above-described conventional technology does not have a device for detecting an abnormal voltage and prevents LED breakdown. Therefore, a metal oxide semicondcutor (MOS) field effect transistor (FET) and a light emitting diode (LED) are damaged and cannot be used. There was a big problem.

Also, in the past, in most lighting devices including LEDs, if only voltage is controlled or only current is controlled, voltage resonance may occur or current resonance may occur due to circuit configuration with a load (LED), resulting in vibration of LED light due to resonance. There is a big problem that the phenomenon occurs.

The present invention has been made to solve the above problems of the prior art, the first object is provided with a current detection control unit, voltage detection control unit and the operation control unit and the detection current stabilization unit, the second object is It is designed to improve the efficiency of LED lighting circuits operating at 320V or higher by the configuration, and the third purpose is to prevent breakage of metal oxide semicondcutor (MOS) field effect transistor (FET) and light emitting diode (LED). The fourth purpose is to protect the LED from damage and danger by preventing overload and overvoltage on the LED by detecting and controlling both voltage and current.The fifth purpose is to simultaneously control voltage and current. This is to prevent voltage resonance or current resonance to maintain stabilized light. The sixth purpose is to increase the efficiency of light. At the same time, the efficiency of the power supply can be increased, so that the effect of power saving can be expected.The seventh purpose is to significantly improve the quality and reliability of the product, thereby allowing the consumer to plant a good image. Provide a lighting circuit.

In order to achieve the above object, the present invention provides a constant power type LED lighting circuit connected to a power factor correction circuit (PFC), wherein the constant power type LED lighting circuit includes a current monitor for detecting a current flowing through the LED module. A current detection control unit which supplies a current unit of a comparator circuit (hybrid chip) through a monitor and a first photo coupler to detect and control current; A voltage detection control unit which detects the voltage across the LED module through a second photo coupler and supplies the voltage to the voltage of the comparator circuit and simultaneously detects the voltage across the LED module and supplies the voltage to the voltage of the comparator circuit; An arithmetic controller provided with a comparator for operating in a circuit so as to simultaneously control the values detected by the current detection controller and the voltage detection controller; And a detection current stabilizer for detecting damage of a metal oxide semicondcutor (MOS) field effect transistor (FET) and a light emitting diode (LED) upon detecting an abnormality by detecting a value of a flowing current amount. A power LED lighting circuit is provided.

As described in detail above, the present invention provides a current detection controller, a voltage detection controller, an operation controller, and a detection current stabilizer.

The present invention is to improve the efficiency of the LED lighting circuit operating in more than 320V by the above technical configuration.

In addition, the present invention is to prevent the damage of the metal oxide semicondcutor (MOS) field effect transistor (FET) and light emitting diode (LED).

In addition, the present invention is to protect the LED from damage and risk by preventing overload and overvoltage of the LED by detecting and controlling both voltage and current.

In addition, the present invention is to maintain the stabilized light by preventing voltage resonance or current resonance by performing voltage control and current control at the same time.

In addition, the present invention can increase the efficiency of the light and at the same time increase the efficiency of the power supply device to expect the effect of power saving.

The present invention is a very useful invention that can significantly improve the quality and reliability of the product due to the above-described effect so that consumers can plant a good image.

Hereinafter, described in detail with reference to the accompanying drawings a preferred embodiment of the present invention for achieving this effect are as follows.

The electrostatic type LED lighting circuit applied to the present invention is configured as shown in FIG.

In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

The following terms are terms set in consideration of functions in the present invention, which may vary depending on the intention or custom of the producer, and their definitions should be made based on the contents throughout the specification.

First, the present invention is a constant power type LED lighting circuit connected to a power factor correction circuit (PFC) (1), the constant power type LED lighting circuit, the current for detecting the current flowing in the LED module 60 A current detection control unit 70 is provided to supply a current unit of a comparator circuit (hybrid chip) through a current monitor 71 and a first photo coupler 72 to detect and control a current.

In addition, the present invention detects the voltage across the LED module 60 through the second photo coupler (81) and supplies the voltage to the voltage of the comparator circuit and at the same time detects the voltage across the LED module (60) comparator circuit And a voltage detection control unit 80 for supplying the voltage to the voltage unit.

In addition, the present invention includes an operation control unit 90 having a comparator 91 for calculating in a circuit so as to simultaneously control the value detected by the current detection control unit 70 and the voltage detection control unit 80.

In particular, the present invention is provided with a detection current stabilizer 100 for detecting the value of the amount of current flowing to prevent damage of the metal oxide semicondcutor (MOS) field effect transistor (FET) and light emitting diode (LED) when abnormality is detected. To provide an electrostatic type LED lighting circuit.

The detection current stabilizer 100 applied to the present invention includes an R25 resistor that detects an abnormality of a current value flowing through the R25 resistor, an R15 resistor that transmits a current amount value detected by the R25 resistor to a C13 capacitor, and the R15 resistor has an overcurrent. It is provided with the C13 capacitor which stabilizes by supplying a detected thing to a comparator.

On the other hand, the present invention may be variously modified and may take various forms in applying the above configuration.

And it is to be understood that the invention is not limited to the specific forms referred to in the above description, but rather includes all modifications, equivalents and substitutions within the spirit and scope of the invention as defined by the appended claims. It should be understood that.

Referring to the operation and effect of the present invention electrostatic power type LED lighting circuit configured as described above are as follows.

First of all, the present invention is to improve the efficiency of the LED lighting circuit operating in more than 320V and also to prevent damage to the metal oxide semicondcutor (MOS) field effect transistor (FET) and light emitting diode (LED). It would be.

In more detail, first, the present invention controls the current by the current detection control unit 70.

That is, the current monitor 71 detects the current flowing through the LED module 60 and supplies the current to the current portion of the comparator circuit (hybrid chip) through the first photo coupler 72. Detection control.

The present invention provides an effect that can solve the problem of breakage of the LED module 60 by a technical action as described above.

After that, the voltage detection control unit 80 detects the voltage.

That is, the voltage across the LED module 60 is detected through the second photo coupler 81 and supplied to the voltage unit of the comparator circuit to detect and control the voltage.

The present invention is to provide an effect that can prevent the shaking of light due to overvoltage and voltage fluctuation by the above technical action, in particular to prevent voltage resonance or current resonance by simultaneously performing voltage control and current control It is to keep the light stabilized.

Subsequently, a value detected by the current detection control unit 70 and the voltage detection control unit 80 is calculated by the comparator 82 circuit to provide a constant power control circuit capable of simultaneously controlling the current and the voltage.

The present invention can increase the efficiency of the light by the above technical action, can increase the efficiency of the power supply device has the advantage of seeing the effect of power saving.

In addition, the present invention detects the value of the amount of current flowing through the detection current stabilization unit 100 to prevent damage to the metal oxide semicondcutor (MOS) FET (Field Effect Transistor) and light emitting diode (LED) during abnormal detection Will provide an effect.

In particular, the detection current stabilization unit 100 is a R25 resistor for detecting an abnormality of the current value flowing, a R15 resistor for transmitting the current amount value detected by the R25 resistor to the C13 capacitor, and the R15 resistor is a comparator that the overcurrent is detected It is provided with a C13 capacitor to be stabilized by supplying it can be expected to the above stabilization effect.

In addition, the present invention can set the timing by using the R15 resistor and the C13 capacitor, which has the advantage of being able to control the signal input to the comparator at a suitable time.

The technical idea of the electrostatic type LED lighting circuit of the present invention is that the same result can be repeatedly carried out, and in particular, by implementing the present invention, it is possible to promote technology development and contribute to industrial development, which is worth protecting.

1 is a circuit diagram of a conventional LED lighting driving circuit.

Figure 2 is a constant power LED lighting circuit diagram applied to the present invention.

<Explanation of symbols for the main parts of the drawings>

70: current detection control unit

80: voltage detection control unit

90: operation control unit

100: detection current stabilization unit

Claims (2)

delete The constant power type LED lighting circuit and the power factor correction circuit are connected to a power factor correction circuit (PFC) (1) which is outputted by switching between an inductance and a switching element through a rectifier connected to an AC input power unit to improve the power factor. Connected to the output unit, the current unit of the comparator circuit (hybrid chip) through the current monitor (Current Monitor) 71 and the first photo coupler (72) for detecting the current flowing through the LED module 60 A current detection control unit 70 for supplying and detecting and controlling current; It is connected to the current detection control unit, and detects the voltage across the LED module 60 through the second photo coupler (81) to supply to the voltage of the comparator circuit and at the same time the voltage across the LED module 60 A voltage detection control unit 80 which detects and supplies the detected voltage to the voltage unit of the comparator circuit; An operation control unit 90 connected to the (-) end of the LED module and having a comparator 91 that operates in a circuit to simultaneously control a value detected by the current detection control unit 70 and the voltage detection control unit 80. ); MOS (Metal Oxide Semicondcutor) FET (Field Effect Transistor) and LED connected to (-) of LED module and (-) of power supply when abnormality is detected by detecting the value of the current flowing through the resistor. In the constant power type LED lighting circuit provided with: a detection current stabilizer (100) for preventing damage to the LED module 60, which is a light emitting diode, The detection current stabilizer 100, An R25 resistor that detects an abnormality in the current value that is connected to a metal oxide semicondcutor (MOS) field effect transistor (FET), an R15 resistor that is connected to the R25 resistor and transfers the amount of current detected by the R25 resistor to a C13 capacitor; The R15 resistor is connected to the C13 capacitor for stabilizing by supplying a comparator to the detection of the overcurrent characterized in that the electrostatic type LED lighting circuit.

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