KR101472727B1 - Phase-controlled dimming LED Power Supply - Google Patents

Abstract

The present invention relates to a phase-control LED dimming power supply device. More specifically, the phase-control LED dimming power supply device is capable of controlling LED dimming by simply operating a phase control switch in different phase control ranges using a MICOM program. According to an embodiment of the present invention, the phase-control LED dimming power supply device, which has a phase control switch, a filter unit, a power factor correction unit, a boosting unit, a constant current unit and an LED module, comprises an LED dimming realization unit which is connected to the rear end of the filter unit to detect phase changes by the phase control switch, to adjust a duty by a MICOM (IC3) according to the phase changes, and to adjust brightness of the LED module by applying the duty to an LED drive IC (IC2) included in the constant current unit.

Description

[0001] The present invention relates to a phase-controlled dimming LED power supply,

The present invention relates to a phase control LED dimming power supply, and more particularly, to a phase control LED dimming power supply capable of controlling LED dimming by simply operating a phase control switch in different phase control ranges using a microcomputer program .

Lighting equipment is an indispensable element not only in everyday life but also indispensable in human economic activity, since it increases the amount of time people can work.

It is very important that the illumination device is easily controlled on / off, and furthermore, it is important to control the brightness.

The lighting apparatus using electricity has been favorably used due to its advantage of easy control, and has been improved in use more conveniently. Recently, a light emitting diode (LED) has been widely used as a light source while consuming less power.

There are AC (alternating current) and DC (direct current) in human use, and LED uses DC (direct current) as operating power.

1 is a block diagram illustrating such a phase controlled LED dimming power supply.

1, the phase control switch 1, the lightning protection and filter unit 2, the rectifying unit 3, the smoothing and power factor correction unit 4, the voltage boost unit 5, the smoothing unit 6, A delay unit 7, a constant current unit 80, a filter unit 9, and an LED module 10.

The phase control switch 1 is a switch for controlling the phase of the AC input power source.

The lightning protection unit of the lightning protection and filter unit 2 uses a varistor, a thermistor, and other components to transmit the lightning voltage inputted to the AC power line to the AC power line again. The filter circuit protects the power supply circuit by minimizing the incoming voltage and prevents the noise due to the specific frequency generated by the power supply device from being transmitted to the AC power supply line due to the capacitance value of the coil (line filter, picking coil, etc.) and the capacitor.

The rectifying unit 3 converts an AC voltage input from the outside into a DC voltage required for the power supply unit and the LED module 10. [

The smoothing part of the smoothing and power factor correcting part 4 smoothens the pulsation included in the DC voltage output from the rectifying part 3 by using a capacitor and the power factor correcting part corrects the power factor converted by the coil or capacitor of the power source device .

At this time, when the capacitance value of the capacitor is high, the power factor is lowered.

More specifically, the reverse current correction unit uses a coil or a capacitor to suppress smoothing and various noise generation at the input terminal of the power supply unit, thereby causing a phase difference between the voltage and the current of the AC input power supply to decrease the power factor value .

The power factor correcting unit makes the power factor value close to 1 so that the current value of the AC power consumption can be minimized.

The boosting unit 5 boosts the voltage by two times that required by the LED module 10 and outputs it.

The smoothing unit 6 smoothes the pulsating voltage generated while outputting a high output voltage from the voltage step-up unit 5 and the delay unit 7 smoothes the voltage that the LED module 10 can normally operate in the voltage- The operation is delayed so that the constant current section 8 is not operated.

The constant current section 8 detects a voltage induced in the sensing resistor and compares it with a set voltage value to maintain a constant voltage.

The filter unit 9 blocks the transmission of various frequencies (noise) generated in the voltage step-up unit 5 and the constant current unit 8 to the LED module 10 using a coil and a capacitor.

The LED module 10 is formed by connecting LEDs in series and in parallel to the total power consumption of the LED module product, and generates light when AC input power is applied.

The LED dimming power supply device using the conventional phase control switch has the following three problems.

First, it is a phase range problem due to the phase control switch change.

The phase control switch 1 has a different control range for each manufacturer.

For example, if the AC input of the company A is 10V ~ 90V RMS, and the AC input of the company B is 0V ~ 100V, the AC input phase is changed to adjust the brightness of the LED module. It is difficult to implement dimming, and in order to implement regular dimming, it is necessary to change the parts when the phase control switch 1 is changed, and even PCB correction is required, which makes it difficult to manage.

Second, the phase control switch malfunctions.

As described above, the LED power supply uses a filter circuit composed of a coil and a capacitor at the AC input for EMI reduction measures, and EMI is also present inside the phase control switch.

Therefore, the phase control switch connected to the AC input will malfunction if the holding current is insufficient to properly maintain the inductive and capacitive elements of the power supply and the capacitive element and the phase control switch of the power supply, and the input phase is irregular .

The LED module 10, which senses and operates as it is, causes a flicker (flicker) and abnormal operation.

Third, it is a problem of starting in the phase control minimum state.

The initial operation of the power supply unit operates by supplying the PFC controller IC of the reverse current correction unit 4 with an instantaneous supply of power via a high value resistor using a high voltage rectified from the input power source, ) Is supplied with a stable VCC power through an auxiliary winding or the like.

However, when the AC input voltage is the lowest (90 V) and the phase control is the minimum, the rectified voltage is also much lower (see ③ of FIG. 2).

At this time, the voltage that can operate the PFC controller IC is insufficient, and there is a problem in start-up, so that it is possible to start the operation by lowering the high value resistance. However, when the AC input is high and the phase control is maximum, There is a possibility that the IC is damaged due to application of a high voltage.

Korean Patent Laid-Open No. 10-2011-0092884 (Aug. 18, 2011) Korean Patent Publication No. 10-2013-0103263 (September 23, 2013)

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems described above, and it is an object of the present invention to provide a phase control switch which can easily control the LED dimming by operating a phase control switch in different phase control ranges using a microcomputer program, And to provide a phase controlled LED dimming power supply capable of starting the controller IC even when the AC input voltage and phase control are at a minimum.

According to an aspect of the present invention, there is provided a phase control LED dimming power supply device including a phase control switch, a filter unit, a power factor correction unit, a boost unit, a constant current unit, ;

The phase change by the phase control switch is sensed and the phase of the LED is adjusted by the microcomputer IC3 according to the phase change to the LED drive IC IC2 constituting the constant current part to adjust the brightness of the LED module And an LED dimming implementation unit.

According to the solution of the above-described problem, it is possible to control the LED dimming by simply operating the phase control switch in different phase control ranges using the microcomputer program, and to supply the holding current necessary for preventing malfunction of the phase control switch , The controller IC can be started even when the AC input voltage and phase control are minimum.

Figure 1 is a schematic block diagram illustrating a conventional phase controlled LED dimming power supply.
2 is a phase control waveform for explaining a problem of the power supply device shown in FIG.
3 is a schematic block diagram of a phase controlled LED dimming power supply in accordance with an embodiment of the present invention.
4 is an example of a phase control switch malfunction prevention portion shown in FIG. 3 and a peripheral circuit diagram thereof.
5 is an example of the starting unit shown in Fig. 3 and a peripheral circuit diagram thereof.
6 is an example of the LED dimming implement shown in FIG. 3 and its peripheral circuit diagram.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

It is to be noted that the same components of the drawings are denoted by the same reference numerals and symbols as possible even if they are shown in different drawings.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Also, when a part is referred to as "including " an element, it does not exclude other elements unless specifically stated otherwise.

3 is a schematic block diagram of a phase controlled LED dimming power supply in accordance with an embodiment of the present invention.

3, the phase control LED dimming power supply includes a phase control switch 110, a lightning protection and filter unit 120, a rectifying unit 130, a phase control switch malfunction prevention unit 220, an activation unit 140, A smoothing and power factor correction unit 150, a voltage boost unit 160, a smoothing unit 170, a delay unit 180, an LED dimming unit 230, a constant current unit 190, a filter unit 200, (210).

The phase control switch 110 is a switch for controlling the phase of the AC input power.

The lightning strike protection portion of the lightning protection and filter unit 120 uses the components such as the varistor (VRS1 in FIG. 4) and the thermistor (TH1 in FIG. 4) to transmit the lightning voltage inputted to the AC power line again to the AC power line The power supply device circuit is protected by minimizing the voltage applied to the internal circuit of the power supply device and the filter portion is protected by the capacitance value of the coil (line filter (LF4 in Fig. 4), picking coil, etc.) and capacitor (C1 and C24 in Fig. 4) Thereby preventing noise due to a specific frequency generated in the power supply unit from being transmitted to the AC power supply line.

At this time, the allowable voltage of the varistor (VRS1) and the thermistor (TH1) is selected according to the AC input voltage.

The rectifying unit 130 converts an AC voltage input from the outside into a DC voltage required for the power supply unit and the LED module 210 by using a bridge diode (BD1 in FIG. 4).

The phase control switch malfunction prevention unit 220 regularly supplies a predetermined basic holding current to the phase control switch 110 so that the phase control switch 110 can perform phase control normally.

The startup unit 140 amplifies the DC voltage that has passed through the rectifying unit 130 by using a transistor and quickly charges the capacitor using a capacitor and then supplies the amplified DC voltage to a PFC (Power Factor Correction) controller IC constituting the power factor correction unit 150, Thereby allowing the IC to operate at a stable constant voltage.

The smoothing part of the smoothing and power factor correcting part 150 smoothes the pulsation included in the DC voltage output from the rectifying part 130 using a capacitor (C5 in FIG. 4 and FIG. 5) Or the power factor converted by the capacitor.

At this time, when the capacitance value of the capacitor is high, the power factor is lowered.

The boosting unit 160 boosts the voltage by two times that required by the LED module 210 and outputs the boosted voltage.

The smoothing unit 170 smoothes the ripple voltage generated while outputting a high output voltage from the voltage boosting unit 160 and the delay unit 180 adjusts the voltage of the voltage up to a voltage at which the LED module 210 can operate normally in the voltage- The operation is delayed so that the constant current unit 190 does not operate before output.

The LED dimming unit 230 senses the phase change by the phase control switch 110 and adjusts the duty of the phase change by the microcomputer IC3 in FIG. 7 to apply it to the LED drive IC (IC2 in FIG. 7) 210).

7, the oscillation frequency is determined by the internal time constant of the resistor R33, the oscillated frequency is transmitted to the FET Q2, and by the voltage induced in the sensing resistor R13, The duty ratio of the oscillation frequency is determined again.

The current value flowing through the source of the FET Q2 is determined by the duty ratio thus changed, and the current value required for the LED module 210 is determined through the coil L1.

The constant current unit 190 detects the voltage induced in the sensing resistor R13 and compares it with the set voltage value to maintain the constant voltage.

The filter unit 200 blocks the transmission of various frequencies (noise) generated in the voltage step-up unit 160 and the constant current unit 190 to the LED module 210 using the coil L1 and the capacitor C4.

The LED module 210 is formed by connecting LEDs in series and in parallel according to the total power consumption of the LED module product, and generates light when AC power is applied.

4 is an example of a phase control switch malfunction prevention portion shown in FIG. 3 and a peripheral circuit diagram thereof.

The phase control switch 110 requires a basic holding current in order to allow inductive and capacitive problems of the LC filter provided at the power supply input terminal and phase control to operate normally.

Therefore, a circuit capable of supplying a necessary current to a portion where each phase is changed is required.

As shown in FIG. 4, the cathode of the Zener diodes ZD3, ZD6 and ZD10 having different zener voltages is connected to the smoothed DC voltage via the capacitor C5, and the anode is connected to the base of the transistors Q6, Q7 and Q8 To ground.

The drains of the FETs Q10, Q12 and Q16 are connected to the cathodes of the Zener diodes ZD3, ZD6 and ZD10 and the transistors Q6, Q7 and Q8 are connected to the sources of the FETs Q10, Q12 and Q16. And the gates of the FETs Q10, Q12 and Q16 are connected to the gates of the FETs Q10, Q12 and Q16 and the collectors of the transistors Q6, Q7 and Q8 are connected to the emitters of the FETs Q10, So that 5 V is applied.

Since the zener diodes ZD3, ZD6 and ZD10 sense the phase voltage portion below the zener voltage due to the different zener voltages and operate the FETs Q10, Q12 and Q16, the phase control switch 110 is maintained at a constant reference The current can be supplied regularly.

That is, when the input voltage fluctuates, when the voltage is output through the zener diodes ZD3, ZD6, and ZD10, the zener diode outputs a constant voltage up to a zener current of a predetermined limit level.

For example, supposing that Zener voltages of the Zener diodes ZD3, ZD6 and ZD10 are 36V, 24V and 12V, respectively, and when the smoothed DC voltage is 30V through the capacitor C5, current flows through the Zener diode ZD3, The FET Q10 can operate to supply the reference holding current to the phase control switch 110. [

At this time, the holding current value may be different according to the type of the phase control switch 110, and the necessary holding current value can be adjusted by changing the Zener diodes ZD3, ZD6, and ZD10.

5 is an example of the starting unit shown in Fig. 3 and a peripheral circuit diagram thereof.

In the situation where the AC input voltage is low and the phase control is minimum, the starting circuit of the PFC controller IC (IC1) constituting the power factor compensator is insufficient and the starting circuit shown in Fig. 5 is needed.

A diode D11 and a Zener diode ZD7 are connected in series in a reverse direction to a line of a smoothed DC voltage via a bridge diode BD1 and a capacitor C5 and grounded between the diode D11 and the Zener diode ZD7 The base of the transistor Q13 is connected to the emitter of the transistor Q11 and the collector of the transistor Q13 is connected to the collector of the transistor Q11, The collector of the transistor Q11 is commonly connected to the resistors R55 and R54 and the emitter of the transistor Q13 is connected to the Vcc pin of the PFC controller IC1 via the diode D13.

That is, a Darlington circuit of the transistor Q11 and the transistor Q13 is configured to amplify the power and supply the VCC power to the PFC controller IC IC1.

The collector of each of the transistors Q14 and Q15 is connected to the resistors R55 and R54 connected in parallel and the emitters of the transistors Q14 and Q15 are grounded to be connected to the base of the transistor Q14. A diode ZD7 is connected.

The base of the other transistor Q15 is connected to the secondary side of the transformer T1 constituting the voltage boosting unit 160 through the zener diode ZD8 and the diode D8 connected in series in the reverse direction, Capacitors C22 and C31 are connected to both ends of the diode ZD8 to be grounded.

The secondary side of the transformer T1 is connected to the Vcc pin of the PFC controller IC IC1 through the diode D2 and to the ground GND pin of the PFC controller IC IC1 through the capacitor C6. And the gate of the PFC controller IC IC1 is connected to the gate of the FET Q1 and the drain of the FET Q1 is connected to the primary side of the transformer T1 via the coil SB1 do.

In the circuit of the above-described starting unit 140, when the AC input is applied, the voltage of the phase-controlled pulsation through the bridge diode BD1 passes through the diode D11 and the resistors R55 and R54 to the base of the transistor Q11 The transistor Q13, which constitutes a Darlington circuit at the same time, is also operated by applying a constant voltage to amplify the power.

The collector voltage of the transistor Q13 is transferred to the capacitor C6 via the diode D13 and the capacitor C6 is rapidly charged and then the starting voltage is applied to the Vcc pin of the PFC controller IC IC1.

At this time, the voltage is determined by the Zener voltage of the Zener diode ZD7, and the voltage higher than the Zener voltage is passed through the Zener diode ZD7 to operate the transistor Q14, thereby forcibly grounding the base of the transistor Q11 Create an OV.

Therefore, the transistor Q11 does not operate and the transistor Q13 does not operate. Therefore, the starting voltage is not applied to the Vcc pin of the PFC controller IC IC1, and the voltage charged in the capacitor C6 is compensated during this time .

This operation is repeated so that the starting section 140 can operate at a stable constant voltage.

On the other hand, after the PFC controller IC IC1 operates, a pulse is applied to the gate of the FET Q1 to repeat the ON / OFF operation. As a result, energy is accumulated and discharged in the transformer T1, Energy is transferred to the wound secondary side, rectified through the diode D2, and rectified through the capacitor C6 to supply a stable voltage to the Vcc pin of the PFC controller IC (IC1).

After the PFC controller IC IC1 operates normally, it is rectified through the diode D8 and passes through the Zener diode ZD8 and smoothed by the capacitors C22 and C31 at both ends thereof to be applied to the base of the transistor Q15 Thereby operating the transistor Q15.

As a result, the base potential of the transistor Q11 is forcibly grounded, and the transistor Q13 is not operated so that the startup unit 140 is turned off.

Accordingly, it is possible to prevent a power loss caused by the startup unit 140 after the PFC controller IC (IC1) operates normally.

6 is an example of the LED dimming implement shown in FIG. 3 and its peripheral circuit diagram.

The diodes D9 and D10 and the Zener diodes ZD6 connected in parallel at the rear end of the lightning protection and filter unit 120 are connected in series in the reverse direction to be grounded, The other side of the Zener diode ZD6 is connected to the base of the transistor Q8.

The collector of the transistor Q8 is connected to the input pin (pin 2) of the microcomputer IC3 by applying a voltage of 5V and its emitter is grounded.

The output pin of the microcomputer IC3 is connected to the base of the other transistor Q5 and the collector of the transistor Q5 is connected to the LED drive IC IC2 And the collector of the transistor Q5 is connected to the LD (linear dimming) pin of the LED drive IC IC2 through a resistor R38 and is connected to the VDD pin of the transistor Q5 And is grounded.

The microcomputer IC3 is connected to the connector CN6 to easily change and input programs.

The primary side of the transformer T1 is connected to the LED module 210 via the diode D1 and between the capacitor C4 and the coil L1 And a drain of the FET Q2 is connected to the capacitor C4 and the coil L1.

The source of the FET Q2 is connected to the sensing resistor R13 to be grounded and the gate thereof is connected to the gate pin of the LED drive IC IC2 and the RT pin of the LED drive IC IC2 is connected to the resistor R33 Lt; / RTI >

The secondary side of the transformer T1 is connected to the ground pin of the PFC controller IC IC1 through the capacitor C6 while being connected to the Vcc pin of the PFC controller IC IC1 through the diode D2 as described above, The primary side of the transformer T1 is connected to the drive of the FET Q1 via the coil SB1 and the gate of the FET Q1 is connected to the gate Dout pin of the PFV controller IC IC1, The drive and source of Q1 are grounded via resistor R26.

The VF input pin of the PFC controller IC IC1 is grounded through a capacitor C14 and connected to the PWM pin of the LED drive IC IC2. (R5, F8) are connected in series so that they can be divided.

The LED dimming unit 230 may be implemented by a phase control switch 110. When the AC input is converted and applied by the phase control switch 110, the LED dimming unit 230 is rectified through the parallelly connected diodes D9 and D10, The zener diode ZD6 is turned on to operate the transistor Q8.

At this time, the operation of the transistor Q8 is such that the OFF time is short and the ON time is long when the phase control is minimum, and the OFF time is long and the ON time is short when the phase control is the maximum.

Using this principle, the voltage duty of the transistor Q8 also changes according to the change of the phase control, so that the phase change can be detected.

A high / low pulse signal is inputted to the input pin (pin 2) of the microcomputer IC3 according to the operation of the transistor Q8 and the signal is inverted by the program inputted to the microcomputer IC3 To the output pin (pin 3) of the microcomputer (IC3).

If the control range is different for each phase control switch 110, an input signal is applied to the input pin of the microcomputer IC1 to check ON time and OFF time in the minimum state and the maximum state, And the connector CN6 can be connected to easily change it.

When the high pulse signal is outputted through the output pin of the microcomputer IC3, the potential of the collector becomes OV by operating the transistor Q5, so that the LD pin (pin 7) of the LED drive IC (IC2) The FET Q2 connected to the gate pin operates in the same manner as the LED driver IC (IC2), so that the LED driver IC (IC2) The current flowing through the LEDs 210 decreases, and the brightness of the LEDs becomes dark.

Conversely, when the pulse signal is outputted through the output pin of the microcomputer IC3, the transistor Q5 does not operate and the collector of the transistor Q5 is turned off by the voltage outputted from the VDD pin (pin 6) of the LED drive IC IC2 7V) of the LED driver IC (IC2) is high and the LED driver IC (IC2) compares the internal pin 2 potential with the pulse ON time of the gate pin (pin 4) So that the FET Q2 connected to the gate pin operates in the same manner, so that the current flowing through the LED module 210 increases and the brightness of the LED illumination becomes brighter.

As the ON time is longer than the OFF time by detecting the change of the phase control as a result of the change of the duty, the level of the LD pin (pin 7 pin) of the LED drive IC IC2 becomes higher and the LED module 210 becomes brighter As the time becomes longer than the ON time, the level of the LD pin (pin 7) of the LED drive IC (IC2) becomes lower and the LED module 201 becomes darker gradually.

The operation of outputting the DC voltage at the boosting unit 160 during the operation of the next peripheral circuit will now be described. In general, the input voltage of the constant current unit 190 should be input twice as much as the output voltage.

The output voltage of the boosting unit 160 is the sum of the voltage applied to the LED module 210 and the circuit voltage composed of the coil L1, the FET Q2 and the resistor R13, The output voltage of the unit 160 may be changed in level, thereby causing the illumination of the LED module 210 to blink for a short time.

In order to solve this problem, the output voltage of the voltage step-up unit 160 (the input voltage of the constant current unit) must be twice as much as the voltage required by the LED module 210.

The secondary voltage of the transformer T1 constituting the voltage boosting unit 160 supplies power necessary for the PFC controller IC IC1 incorporating the oscillation circuit and the comparator circuit through the diode D2 and the capacitor C6.

An oscillation signal oscillated by the PFC controller IC IC1 is transmitted to the gate of the FET Q1 via the gate pin so that a current flows from the drain to the source and the signal amplified by the FET Q1 flows through the coil SB1, The DC voltage rectified through the capacitor C1 and the capacitor C4 is output.

The duty ratio of the oscillation signal output to the gate pin by the current sense comparator in the PFC controller IC (IC1) using the voltage induced in the resistor R26 by the current flowing from the drain to the source of the FET (Q1) .

The voltage divided by the resistors R5 and R8 controls the duty ratio of the oscillation signal output to the gate pin by the overvoltage comparator within the PFC controller IC IC1 to control the duty ratio of the FET Q1, The DC voltage and the level output to the diode D1 and the capacitor C4 are adjusted.

When the AC power is applied, the DC voltage starts to be output from the voltage booster 160 and the LED module 210 is turned on at the voltage booster 160 The LED drive IC IC2 of the constant current unit 190 first operates before outputting a voltage capable of operating normally.

The Vin pin of the LED drive IC (IC2) operates when DC 10V or more, for example, and an oscillation signal for operating the FET Q2 is outputted to the gate pin, so that the LED module 210 is flickered .

In the present invention, the voltage of the Vin pin of the LED drive IC IC2 is maintained at the low level before the capacitor C14 is charged in the resistor R5, the resistor R8 and the capacitor C14, The internal oscillation circuit of the LED drive IC (IC2) does not operate.

When the capacitor C14 is sufficiently charged, a high voltage is inputted to the VD pin of the LED drive IC IC2 through the diode D4, and the internal oscillation circuit of the LED drive IC operates to output an oscillation signal to the gate pin The FET Q2 is operated and the LED of the LED module 210 is normally illuminated.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. In addition, it is a matter of course that various modifications and variations are possible without departing from the scope of the technical idea of the present invention by anyone having ordinary skill in the art.

110: phase control switch 120: lightning protection and filter unit
130: rectification part 140:
150: smoothing and power factor correcting unit 160:
170: smoothing unit 180: delay unit
190: Constant current section 200: Filter section
210: LED module 220: phase control switch malfunction prevention part
230: LED dimming implementation IC1: PFC controller IC
IC2; LED drive IC IC3: Microcomputer

Claims (7)

A phase control LED dimming power supply comprising a phase control switch, a filter, a power factor correcting part, a boosting part, a constant current part and an LED module;
The phase change by the phase control switch is sensed and the phase of the LED is adjusted by the microcomputer IC3 according to the phase change to the LED drive IC IC2 constituting the constant current part to adjust the brightness of the LED module Wherein the LED dimming implementation comprises a LED dimming implementation. The method according to claim 1,
In the LED dimming implementation unit, the diodes D9 and D10 and the Zener diode ZD6 connected in parallel to the rear end of the filter unit are connected in series and connected in the reverse direction, and the other side of the Zener diode ZD6 is connected to the base of the transistor Q8 And,
The collector of the transistor Q8 is connected to the input pin of the microcomputer IC3 and its emitter is grounded,
The output pin of the microcomputer IC3 is connected to the base of the other transistor Q5 and the collector of the transistor Q5 is connected to the VDD pin of the LED drive IC IC2, Is connected to the LD (linear dimming) pin of the LED drive IC (IC2) and is connected to the emitter of the transistor (Q5) through the capacitor (C9) and grounded. 3. The method of claim 2,
When the phase control is the lowest, the transistor Q8 has a short OFF time and a long ON time. When the phase control is at its maximum, the OFF time is long and the ON time is short.
When the high / low pulse signal is input to the input pin, the microcomputer IC3 inverts the pulse signal by the program input to the microcomputer IC3 and outputs the inverted pulse signal to the output pin. Control LED dimming power supply. The method according to claim 1,
And a phase control switch malfunction prevention unit connected to a downstream end of the filter unit to periodically supply a predetermined basic holding current to the phase control switch,
The phase control switch malfunction prevention unit is configured such that one side of a zener diode ZD3, ZD6, ZD10 having different Zener voltages is connected to a smoothed DC voltage via a capacitor C5 at the rear end of the filter unit and the other side is connected to a transistor Q6, Q7, Q8 And is grounded,
The drains of the FETs Q10, Q12 and Q16 are connected to one side of the Zener diodes ZD3, ZD6 and ZD10 and the emitters of the transistors Q6, Q7 and Q8 are connected to the sources of the FETs Q10, Q12 and Q16. The collectors of the transistors Q6, Q7 and Q8 are connected to the gates of the FETs Q10, Q12 and Q16. The gates of the FETs Q10, Q12 and Q16 are connected to each other, Voltage is applied to the phase-controlled LED dimming power supply. The method according to claim 1,
The DC voltage that has passed through the filter unit is amplified using a transistor, rapidly charged using a capacitor, and then supplied to a PFC (Power Factor Correction) controller IC1 constituting a power factor correcting unit, so that the PFC controller IC IC1 operates with a stable constant voltage Wherein the phase control LED dimming power supply further comprises a start-up unit. 6. The method of claim 5,
The starter has a diode D11 and a zener diode ZD7 connected in series in a reverse direction to a DC voltage line and a resistor R55 and a resistor R54 are connected in parallel between the diode D11 and the zener diode ZD7 The base of the transistor Q13 is connected to the emitter of the transistor Q11 and the collector of the transistor Q13 is connected to the collector of the transistor Q11 and the resistors R55, R54 and the emitter of the transistor Q13 is connected to the Vcc pin of the PFC controller IC1 through the diode D13 and the ground pin of the PFC controller IC IC1 through the capacitor C6 Wherein the phase control LED dimming power supply comprises: The method according to claim 6,
The collector of each of the transistors Q14 and Q15 is connected to the resistors R55 and R54 connected in parallel and the emitters of the transistors Q14 and Q15 are grounded to be connected to the base of the transistor Q14, A diode ZD7 is connected,
The base of the other transistor Q15 is connected to a secondary side of the transformer T1 constituting the voltage boosting unit 160 through a zener diode ZD8 and a diode D8 connected in series in the reverse direction,
The secondary side of the transformer T1 is connected to the Vcc pin of the PFC controller IC IC1 via a diode D2 and the gate of the PFC controller IC IC1 is connected to the gate of the FET Q1 , And the drain of the FET (Q1) is connected to the primary side of the transformer (T1) through the coil (SB1).

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