KR101597149B1 - Delay Lights Out Device For Light Emitting Diode Lamp - Google Patents

Abstract

The present invention relates to a delay lights out device for a light emitting diode (LED) lamp which comprises: a time setting unit which sets a set-up time to delay a lights out time of an LED lamp after a switch (SW) is turned off; a set-up time detecting unit made up of a main control unit (MCU) which converts the set-up time based on the amount of electric current applied from the time setting unit, and outputs current during the converted set-up time; a lights out delaying unit which comprises: a photo-coupler (PC) which applies the current applied from the set-up time detecting unit, to the LED lamp during the set-up time to light the LED lamp, and is operated by the current inputted from the time setting unit, and is turned off when the set-up time is over after the switch (SW) is off, a resistance (R2) which is connected to the input line in the time setting unit to control input currents, and is also connected to the an input terminal of a photo-coupler (PC), a resistance (R3) connected to an output terminal of the photo-coupler (PC) to control output currents, and a triac (TD) connected to the feedback terminal of the photo-coupler (PC). The configuration of the present invention has benefits, such as allowing the user to check obstacles that are present within the motion path since the LED lamp is turned on during the set-up time after the switch is turned off, and allowing variable the delay time set-ups depending on the user′s preference or the length of motion path after the switch is turned off.

Description

BACKGROUND OF THE INVENTION Field of the Invention [0001] The present invention relates to a Delay Lights Out Device for a Light Emitting Diode Lamp,

More particularly, the present invention relates to an apparatus for reducing the delay time of an LED lighting fixture used in an LED lighting fixture and more particularly to a lighting fixture retardation lighting fixture which is mounted on an LED lighting fixture and comprises a photocoupler and a triac non- Off delayed by a user when the set time for the user to move is turned off.

As the technology related to light emitting diodes (LEDs) rapidly developed, white LEDs emitting white light by using blue LEDs and phosphors appeared. Such white LEDs are extremely small in size compared to conventional light sources, It is an environmentally friendly illumination light source that does not use mercury and discharge gas and is a promising alternative to existing illumination light sources because it has low power, has a long life span, does not emit harmful waves such as ultraviolet rays, and does not use mercury and discharge gas.

Recently, as the era of low carbon green growth has come, international green environment movement has been developed. In line with these international trends, the Korean government has established a 5-year green growth plan and actively supports it.

Of these low-carbon, green growth sectors, LEDs are in the spotlight as products that meet the trend of low-carbon green growth due to high conversion efficiency of light, low mercury consumption and low carbon dioxide emission.

The LED is widely used for a general lighting, a building decoration, a mood, a vehicle, a traffic light, an indoor and outdoor electric signboard, a guidance light, a warning light, a light source for various security devices, and a light source for sterilizing or disinfecting.

In general, LED lighting equipment is widely used as a main lighting device because it is able to control the brightness of the LED by changing the current supplied based on a constant voltage by converting AC into DC.

Accordingly, according to Korean Patent Publication No. 10-1266932, an LED light bulb power control device (May 16, 2013), which replaces a lighting device such as a fluorescent lamp and employs an LED as a light source,

And an overcurrent protection fuse for protecting the circuit from an instantaneous overvoltage or a surge current of an alternating current applied from a power source for supplying the LED bulb to one of input lines of an input AC power source, An AC filter unit including an overvoltage protection varistor configured in parallel with an AC power source configured and arranged at the rear of the fuse; A plurality of capacitors C1, C2, ..., Cn-1, and Cn configured in parallel with an input line connected to a fuse, A voltage regulator configured in series with the input line connected to the fuse and constituted by a resistor for discharging the capacitor; An AC / DC converter configured to receive an AC current from the voltage regulator and convert the AC current into a DC current, a bridge rectifier circuit configured to convert the dropped AC into a DC, and a rectifier diode; The direct current applied by the AC / DC converter is limited to the current of the LED light source, and the current is configured in parallel with the cathode of the diode D1 and the diode D2 of the bridge rectifier circuit, And a current regulator composed of a plurality of resistors R2, R3 .... RN-1, RN.

The power source control device of the LED bulb of the related art has a problem in that when the user turns off the LED light at the time of sleep and the LED light goes out at the same time as the switch is turned off, There is a problem that it must be moved sensibly to a place.

Further, in the prior art, when the user leaves the room after going out or leaving the room, there is a problem that the user must wait until the pupil expands in order to prevent the user from colliding with the obstacle or colliding with the obstacle due to the movement line being dark have.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-described problems, and it is an object of the present invention to provide an apparatus and a method for controlling a switch SW by using a central processing unit, a potentiometer, a photocoupler and a triac, After the switch SW is turned off, the user can set the setting time of the light-off delay because the LED light is not turned off for the set time, and then the obstacle etc. in the moving wire is checked after the switch SW is turned off And a light-off delay-light-off device having a light-off delay function which is turned off in a state in which the LED illumination light is turned on for a predetermined set time.

The present invention relates to a delay light-off device for an LED light fixture, comprising: a time setting unit for setting a setting time for delaying the light-off time of an LED illumination light after the switch SW is turned off; And a central control unit (MCU) for converting the set time according to the amount of current applied by the time setting unit and outputting the current for the set time converted; The current applied by the set time sensing unit is applied to the LED illuminating lamp for the set time, and the LED illuminating lamp is turned on. When the set time is elapsed after the switch SW is turned off, And a photocoupler (PC) connected in series.

Further, in the present invention, the time setting unit is constituted by a variable resistor (P) capable of changing the magnitude of the resistance.

Further, the present invention is characterized in that the delay OFF part is connected to the input line in the time setting part and is operated by a current applied from the resistor R2 and the resistor R2 connected to the input terminal of the photo-coupler (PC) (TR) connected to the AC power of the power source while being connected to the output terminal of the photocoupler (PC) and the photocoupler (PC) and connected to the feedback terminal of the photocoupler (PC) : Triac).

In the present invention, when the central control unit (MCU) detects the off state of the switch SW and converts the set time for the off delay of the time setting unit and the switch SW is turned off, .

In addition, the present invention may further include a constant voltage setting unit in front of the set time sensing unit, wherein the constant voltage setting unit includes a capacitor C1 configured in parallel to the input line to which the constant voltage setting unit is connected, a capacitor C1 configured in series with the input line, And a zener diode ZD and a capacitor C2 which are sequentially arranged in parallel to the positive and negative electrodes of the bridge rectification circuit BD of the voltage rectification section are formed behind the resistor R1.

The LED light fixture delay light-off device according to the present invention has an effect that the user can identify an obstacle or the like in the mobile line because the LED light is turned on during the set time after the switch is turned off.

In addition, the present invention has an effect that the illumination lamp can be installed and mounted in the LED illumination lamp, so that it is also applicable to the LED illumination lamp installed in the present invention.

Further, the present invention has an effect that the delay time can be set according to the user's preference or the length of the moving copper wire after the switch is turned off by the time setting unit.

Further, according to the present invention, if the delay time is not set in the time setting unit, there is an effect that the LED illumination light is turned off at the same time when the switch is turned off.

Further, according to the present invention, the use of the non-contact relay of the photocoupler and the triac has the effect of ensuring the delayed light emission and preventing the mechanical failure.

Further, the present invention has an effect that the delay time switch and the LED light OFF switch use one switch, i.e., a single power source.

1 is a configuration diagram of a power control device for an LED bulb of the related art;
Fig. 2 is a block diagram of an LED illumination light delay light-off device according to the present invention. Fig.
Fig. 3 is a block diagram of an apparatus for delaying the illumination light of the present invention;
4 is a view showing the internal structure of the photo coupler of the present invention.

The configuration and operation according to the embodiment of the present invention will be described in more detail with reference to FIGS. 2 and 4 attached hereto.

The apparatus includes a voltage rectifying unit (11) for converting an AC input from a power source into a direct current, a constant voltage setting unit (12) for adjusting a DC voltage applied from the voltage rectifying unit (11) A set time detection unit 13 for detecting the off time of the switch SW by the current applied by the setting unit 12 and detecting the set time for the off delay, A time setting unit 14 for setting the light-off time of the LED light 100 and a delay light-off unit 15 for lighting the LED light 100 during the set time.

The voltage rectifying unit 11 is composed of a bridge rectifier (BD) composed of rectifying diodes D1, D2, D3 and D4 and receives an AC voltage applied from a power source, ) Voltage and outputs it.

The bridge rectification circuit BD of the voltage rectification unit 11 is configured such that the anode of the diode D1 and the cathode of the diode D2 are connected to the power supply line of the AC power supply at the same time and the anode of the diode D3 And the anode of the diode D4 are simultaneously connected to the remaining power line of the AC power source and the cathodes of the diode D1 and the diode D3 are connected to the positive voltage setting unit 12, And the positive electrodes of the diode D2 and the diode D4 are connected to the negative electrode of the constant voltage setting unit 12 at the same time.

That is, even if the supply voltage supplied to the voltage rectifying unit 11 is a direct current voltage or an alternating voltage, the voltage outputted by the bridge rectifying circuit BD is a direct current voltage, and the polarity of the direct current voltage is reversely connected The voltage output through the bridge rectification circuit BD has a DC voltage.

The constant voltage setting unit 12 inputs the anode of the direct current applied from the voltage rectifying unit 11 and the cathode of the direct current applied from the voltage rectifying unit 11 to drop and adjust the voltage with respect to the inputted direct current, (13).

The constant voltage setting unit 12 applies the applied DC voltage to the set time sensing unit 13 and smoothing the input DC voltage to a constant voltage and supplies the constant voltage to the diode D1 of the voltage rectifying unit 11 and the cathode of the diode D3, A capacitor C1 configured in parallel with the input line connected to the diode D1 and a diode D1 connected to the input terminal of the voltage rectifying unit 11 and an input line connected to the cathode of the diode D3, A Zener diode (ZD: Zener Diode) and a capacitor C2, which are sequentially arranged in parallel to the positive and negative electrodes of the bridge rectification circuit BD of the voltage rectifying unit 11, .

The capacitor C1 and the resistor R1 convert the voltage applied from the constant voltage setting unit 12 to a voltage suitable for operation of the set time sensing unit 13 and the zener diode ZD converts the transient voltage to a voltage -Pass) to the constant voltage and the capacitor C2 to smooth the constant voltage.

The constant voltage setting unit 12 is constituted by an RC power supply circuit for generating a power supply voltage so that the set time sensing unit 13 can operate properly so that the capacitor C1 matches the appropriate load capacity of the set time sensing unit 13. [ Adjust the DC voltage so that it can do.

The DC current applied to the constant voltage setting unit 12 is stored in the capacitor C1 and charged. Since the DC current in the charged state in the capacitor C1 can not flow, the DC current does not flow, The capacitor R1 is turned on when the DC current charged in the capacitor C1 becomes equal to or higher than a predetermined value to connect the positive electrode and the negative electrode of the capacitor C1 and conduct the capacitor C1, The discharged current is discharged.

The capacitor C1 is composed of a plurality of capacitors in parallel, that is, a capacitor C1 and a capacitor C1-2 (not shown) to finely control the drop of the DC input voltage. The capacitor C1n-1 And a capacitor C1n (not shown) may be formed in parallel. In this case, the voltage value dropping according to the capacitance of the capacitor can be finely adjusted by using the capacitor C1 as the main axis.

The DC current applied to the constant voltage setting unit 12 is stored and charged in the capacitor C1 and the extra DC current remaining charged in the capacitor C1 is stored in the capacitor C1-2, C1n ... C1n-1, and C1n are charged in the capacitor C1, the capacitor C1-2, the capacitor C1n-1, and the capacitor C1n, Since the charged DC current can not flow, the DC current does not flow.

At this time, the resistor R1 conducts when the DC current charged in the capacitors C1, C1-2 ... C1n-1, C1n becomes a predetermined value or more, The capacitors C1, C1-2, ..., C1n-1, and C1n are turned on while the positive and negative electrodes of the capacitors C1, C1-2, 1, C1n are discharged.

That is, the alternating current applied to the constant voltage setting unit 12 is sequentially charged and discharged in the order of the capacitor C1 → the capacitor C1-2, the capacitor C1n-1 → the capacitor C1n, .

The zener diode ZD is connected in parallel to the cathode of the bridge rectification circuit BD and the anode of the DC rectifier circuit BD and the cathode of the bridge rectification circuit BD to output the voltage of the direct current output from the resistor R1 It is able to regulate a specific voltage and flow the current to a breakdown. Therefore, when a constant reverse voltage is applied due to its characteristics, the current flows to lower the resistance so that the voltage does not rise at the point.

The Zener diode (ZD) flows the current like an ideal diode in the forward direction. In the reverse direction, however, the current flows only above the breakdown voltage. Since the Zener diode is a 5.1V zener diode, when the voltage is 5V, the current hardly flows. All the current is bypassed through the Zener diode ZD and is discharged to the ground GND,

When the normal voltage is applied to the positive electrode of the microcontroller unit (MCU) of the set time sensing unit 13, the Zener diode ZD does not conduct current, When an overvoltage is generated on the anode of the MCU, the overvoltage current is bypassed through the Zener diode ZD and is discharged to the ground GND, And the voltage is stabilized without increasing the voltage of the direct current of the battery.

Therefore, even if there is a voltage fluctuation in the DC supplied from the bridge rectification circuit (BD) of the voltage rectification unit (11), stable power is supplied to the central control unit (MCU) as a load. Can be improved.

The Zener diode ZD may be composed of a plurality of Zener diodes ZD1 and ZD2 in series and a Zener diode ZDn-1 and a Zener diode ZDn. In this case, Zener diode ZD2 Zener diode ZDn-1 Zener diode ZDn Zener diode ZDn Zener diode ZDn Zener diode ZDn Zener diode ZDn Zener diode ZDn Zener diode ZDn Zener diode The fine voltage can be adjusted as it goes from the zener diode ZD1 to the zener diode ZD2 via the zener diode ZD2.

That is, the overvoltage current that can not be stabilized by the zener diode ZD1 is further stabilized by the diode ZD2, and the overvoltage current which is not stabilized by the zener diode ZD2 is sequentially supplied to the zener diode ZD3. ZDn).

The overvoltage DC current applied to the constant voltage setting unit 12 is sequentially energized in the order of Zener diode ZD1 → Zener diode ZD2 ... Zener diode ZDn-1 → Zener diode ZDn, The micro voltage is adjusted and stabilized from ZD1 to Zener diode ZDn so that the adjusted microvoltage is applied to the central control unit MCU.

If the DC supplied to the central control unit MCU is not supplied with the overvoltage, that is, if the Zener diodes ZD1, ZD2, ... ZDn-1, ZDn are not turned on, The direct current does not flow through the zener diodes ZD1, ZD2 .... ZDn-1, ZDn.

The capacitor C2 is connected in parallel to the positive and negative electrodes of the bridge rectification circuit BD at the rear of the Zener diode ZD. The capacitor C2 adjusts the DC level of the power supplied from the voltage rectifying unit 11, The voltage rectifier 11 absorbs the ripple which is a regular modulation of the voltage and controls the DC level of the power supplied from the voltage rectifier 11 to apply it to the set time sensing unit 13. The bridge rectifier circuit BD In other words, the direct current output from the rectifier can not be used as it is a pulsating current that contains a lot of ripples. Therefore, the smoothing circuit smoothes the smoothed direct current through the smoothing circuit, that is, the capacitor C2 to reduce the ripple.

The capacitor C2 is configured between the voltage rectifying unit 11 and the set time sensing unit 13 in order to remove the ripple included in the direct current outputted from the bridge rectifying circuit BD of the voltage rectifying unit 11, Since the driving voltage of the time sensing unit 13 is low, the capacitor C2 is connected in parallel to the DC power source.

The set time sensing unit 13 senses whether the switch SW is turned off by the current applied from the constant voltage setting unit 12 and detects a set time for the turn off delay of the time setting unit 14 When the switch SW is turned off, the set time is converted according to the amount of current applied from a potentiometer (P) of the time setting unit 14 and a current is applied to the delay off unit 15 during the converted set time And a central control unit (MCU).

The switch SW is installed on a wall surface of an entrance door of a room or a living room and is electrically connected to the central control unit MCU by an electric wire by lighting or lighting the LED light 100 by operation.

The central control unit MCU is connected to the positive and negative terminals of the constant voltage setting unit 12 and is driven by a power source applied from the constant voltage setting unit 12 and the input and output lines of the switch SW are connected to each other, And detects the amount of current input by adjusting the variable resistor P connected to the variable resistor P of the time setting unit 14 to detect the amount of the current inputted to the LED light The switch SW is turned off by converting the set time set for the extinction delay of the switch 100 to output a current to the photocoupler (PC: Photocoupler) of the delay-off unit 15 during the set time.

The time setting unit 14 sets a set time for delaying the light-off time of the LED illumination light 100 after the switch SW of the set time sensing unit 13 is turned off, And the variable resistor P is configured so that the size of the resistance of the variable resistor P can be changed by the user.

The variable resistor P is connected between the positive terminal of the constant voltage regulator 12 and the positive terminal of the bridge rectifier circuit BD of the voltage rectifier 11 and the intermediate terminal is connected to the positive terminal of the set time detector 13 It is connected to the central control unit (MCU) and the output terminal is grounded (GND).

During the time corresponding to the amount of current due to the changed resistance of the variable resistor P, that is, during the setting time for delaying the unlit time of the LED illumination lamp 100, the central control processing unit (MCU) Outputs a current to the delay-off unit 15 or the photocoupler PC.

When the positive polarity current of the bridge rectifier circuit BD of the voltage rectifying unit 11 is input to the variable resistor P, the variable resistor P is set by the user by the rotation of the intermediate terminal The current corresponding to the resistance changed by the set time is fed back to the central control unit (MCU) through the intermediate terminal, and the central control unit (MCU) converts the time corresponding to the amount of current applied in the variable resistor And outputs it to the delay-off unit 15 or the photocoupler PC during the converted time, that is, the set time.

The variable resistor P has a lead terminal, that is, three terminals for providing electrical contacts. The internal structure of the variable resistor P has a constant resistance value by forming a carbon body on the nonconductor formed flat from one side to the other side, Is rotatable between the flatly distributed carbon bodies by the human hand, and the resistance value changes according to the rotational position of the intermediate terminal, and the magnitude of the current flowing due to the change in resistance is changed.

The delay OFF unit 15 applies a current to the LED illumination lamp 100 for a predetermined time period set in the set time unit 14 to light the LED illumination lamp 100 and to set the elapsed time after the switch SW is turned OFF The LED illumination lamp 100 is turned off.

The delay OFF unit 15 is connected to the input line in the time setting unit 14 and adjusts the input current and supplies the current to the input terminal of the photocoupler PC by a resistor R2 connected to the input terminal of the photo- The photocoupler (PC) and the photocoupler (PC) are connected to the output terminal and are connected to the feedback terminal of the photocoupler (PC) And a triac (TD) in which a power source is applied to the LED light 100.

The switch SW is turned off in the state that the LED illumination light 100 is turned on so that the illuminance of the surrounding environment of the LED illumination light 100 is bright, Since the function may not work well, we use a photo coupler (PC) to solve this problem and ensure the switching function during set time.

The photocoupler PC is used for on / off of the set time applied by the central control unit MCU. In the closed space, the anode is connected to the resistor R2 and the cathode is connected to the external ground Emitting diode (LD), which is connected to the ground (GND) and directly converted to light energy, and a light emitting unit (LED), which is spaced apart from the light emitting diode (LD) And a photodiode (PD: Photo Diode) in which an anode is connected to an external AC power source and a cathode is connected to an external resistor R3.

The photocoupler PC has two output states corresponding to ON and OFF of a relay operation and has almost no contact accident and is highly reliable against external conditions such as temperature and humidity, It is a non-contact relay with good mechanical contact and on / off operation is faster and lower voltage than other products. There is no electrical connection between light emitting part and light receiving part, Since the load is transmitted to the emitter of the DC type photocoupler PC according to the present invention without being influenced by the noise through the ground GND since the signal is transmitted only by the ground, In the emitter, the same signal as the input is output.

The photocoupler PC includes a photodiode LD that emits light and receives light emitted from the light emitting diode LD when a current signal applied from the resistor R2 is input to the light emitting diode LD, The photodiode PD is turned on to enter the conduction state and the alternating current of the power source is conducted to the resistor R3 through the photodiode PD.

The triac TD is connected to the AC power source of the power source and the gate of the triac is connected to the resistor R3 connected to the output of the photocoupler PC and the cathode of the triac is connected to the LED illumination lamp 100, And the converter 110 is connected to an LED module 120 composed of a plurality of LEDs.

The resistor R2 converts the DC current applied by the time setting unit 14 into a current suitable for driving the photocoupler PC and the resistor R3 supplies the alternating current of the photocoupler PC When the gate of the triac TD is connected, the alternating current of the power source is conducted to the converter 110 via the triac TD and the current between the positive and negative electrodes of the triac TD is maintained at the The gate is turned off so that the alternating current of the power source is not applied to the converter 110.

The alternating current of the power source is supplied to the converter 110 through the triac TD during the set time of the variable resistor P so that the alternating current of the power source is transmitted through the converter 110 The LED light is applied to the LED module 120 so that the LED light is turned on.

When the photocoupler PC is energized, the alternating current is inputted to the gate of the triac TD through the resistor R3 so that the trigger operation of the triac TD is maintained in the turn on mode, When the coupler PC is disconnected, the trigger operation of the triac TD is also turned off, so that the trigger operation of the triac TD continues until the input current is cut off, The turn-on mode is maintained.

As a result, when the set time of the variable resistor P has elapsed, the trigger operation of the triac TD is interrupted, and the triac TD is turned on and off of the photocoupler PC The AC current is interrupted by the converter 110 due to the interruption of the trigger signal and the LED illumination lamp 100 is turned off.

When the switch SW is on, the central control unit MCU of the set time sensing unit 13 detects that the switch SW is on, The photocoupler PC is maintained in a state of being in a state of being in a state of being in a state of being in a state of being in a state of being injected into the resistor R2 of the delayed turn- The trigger operation is maintained in the turn on mode so that the AC current of the power source is sequentially supplied to the LED module 120 through the triac TD and the converter 110 so that the LED illumination light 100 is turned on State.

The present invention comprises a central control unit (MCU), a photocoupler (PC), a triac (TD), and the like. When the LED illumination lamp 100 is lit, that is, when the switch SW is on The lighting of the LED illumination lamp 100 is continuously turned on until the set time.

The converter 110 of the LED illumination lamp 100 is connected to the other power supply line of the alternating current and is connected to the LED module 120 composed of the converter 110 and a plurality of LEDs and supplies the inputted current to the LED module 120. [ And the converter 110 and the LED module 120 are configured for the LED illumination lamp 100, the description thereof will be omitted in the present invention.

Therefore, according to the present invention, since the LED illumination light 100 is turned on for a set time after the switch SW is turned off, the user can check an obstacle or the like in the movement line, The delay time can be set in accordance with the length of the moving copper wire after the switch is turned off and the use of the contactless relay such as the photocoupler (PC) and the triac (TD) Otherwise, if the delay time is not set, the LED illumination lamp 100 is turned off at the same time as the switch SW is turned off, and the delay time switch and the LED no light switch use one switch SW It is effective.

Although the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the equivalents of the claims, as well as the claims.

10: LED illumination light delay off device 11: voltage rectifying part
12: constant voltage setting unit 13: set time detection unit
14: Time setting unit 15: Delayed off unit

Claims (5)

delete delete delete CLAIMS What is claimed is: 1. An apparatus comprising:
And a variable resistor (P) for delaying the turn-off time of the LED illumination light after the switch (SW) is turned off;
The switch SW is connected to the variable resistor P of the time setting unit to sense the amount of the current flowing through the variable resistor P to convert the set time and to be connected to the input and output lines of the switch SW, (MCU) which is driven by a power source which is connected to an anode of the constant voltage setting unit and a constant voltage setting unit when the switch SW is turned off, A set time detection unit configured to detect the set time;
A resistor R2 connected to the input line input by the time setting unit, a light emitting diode LD connected to the resistor R2 and having a cathode connected to an external ground GND and a light emitting diode LD, And a photodiode PD which is operated by the light emitted from the light emitting diode LD and is operated by the current applied from the resistor R2 and is turned off when the set time after the switch SW is elapsed A resistor R3 connected to the output terminal of the photodiode PD for adjusting the output current and connected to the feedback terminal of the photodiode PD and connected to the AC power source of the power source, (TD), and is configured to apply a current, which is applied from the set time sensing unit, to the LED illumination lamp for a preset time period to illuminate the LED illumination lamp.
5. The method of claim 4,
The constant voltage setting unit includes a capacitor C1 configured in parallel to the input line to which the constant voltage is connected, a resistor R1 for discharging the capacitor C1, which is formed in series with the input line, Wherein a Zener diode (ZD) and a capacitor (C2) are formed in parallel in parallel to the positive and negative electrodes of the first and second photodiodes (BD).

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