A switchable three-in-one dimming circuit

Abstract

A shut-off three-in-one dimming circuit relates to the field of lamp control technology. The circuit includes a linearly adjustable input voltage source, a voltage source generating module, an RC filter module, a voltage follower module and a first comparator module. The voltage source generating module is connected to an adjustable input voltage source and then connected to an RC filter module. The RC filter module is connected to a DIM interface. An external dimming signal is received between the DIM interface and a ground GND. The external dimming signal includes a PWM signal, a 0-10V voltage signal and an adjustable resistance voltage signal. The first comparator module includes a first comparator, an RC filter module is connected to the first comparator, and a voltage source generating module is connected to the first comparator via a resistor R9 and a resistor R10. The output end of the first comparator module is connected to a MOS interface. The present invention adds an RC filter module and a first comparator, receives three external dimming signals and can be turned off, and realizes a shut-off three-in-one dimming.

Description

Technical Field

[0001] The present invention relates to the technical field of lamp control, and in particular to a switchable three-in-one dimming circuit. Background Art

[0002] In some lighting control, a dimming circuit is usually added to adjust the brightness of the lamp. There are many types of dimming circuits and dimming modes, but either the circuit design is complex or the dimming mode is single. The complex circuit dimming design not only increases the complexity of the entire LED lamp control system, but also makes it more troublesome to detect once a fault occurs. Although the dimming design with a single dimming mode is much simpler, there are not many options, which brings great limitations to the user experience. The key is that in some dimming mode circuits, it is impossible to achieve a circuit that is both turnable and three-in-one dimming. Summary of the invention

[0003] The object of the present invention is to avoid the deficiencies in the prior art and provide a switchable three-in-one dimming circuit, which is compatible with three dimming signals and can realize the switch-off operation of the lamp.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] Provided is a switchable three-in-one dimming circuit for dimming and switching off a lamp, comprising a linearly adjustable input voltage source, a voltage source generating module, an RC filtering module, a voltage follower module and a first comparator module;

[0006] The input voltage source is connected to the input end of the voltage source generating module, the second output end of the voltage source generating module is connected to the first input end of the RC filter module through a diode D5, the first output end of the RC filter module is connected to the positive input end of the voltage follower module, the output end of the voltage follower module is connected to the REF interface, the REF interface is connected to the lamp, and the second input end of the RC filter module is connected to the DIM interface;

[0007] An external dimming signal is received between the DIM interface and the ground GND, and the external dimming signal includes a PWM signal, a 0-10V voltage signal and an adjustable resistance voltage signal;

[0008] The first comparator module includes a first comparator, the positive input terminal of the first comparator is connected to the second output terminal of the RC filter module, the negative input terminal of the first comparator provides a reference voltage, the first output terminal of the voltage source generating module is connected to the negative input terminal of the first comparator after voltage division by resistors R9 and R10, the output terminal of the first comparator is connected to the MOS interface, and the MOS interface is connected to the lamp.

[0009] Among them, it also includes a second comparator module, which includes a second comparator, the positive input end of the second comparator is connected to the second output end of the RC filter module, the negative input end of the second comparator provides a reference voltage, the first output end of the voltage source generating module is connected to the negative input end of the second comparator after voltage division by resistors R9 and R10, the output end of the second comparator is connected to the OPTO interface, and the OPTO interface is connected to the lamp through an optical coupling.

[0010] A switchable three-in-one dimming circuit according to claim 2, characterized in that: the RC filter module includes a capacitor C7, a resistor R17, a resistor R18 and a resistor R19, the negative electrode of the capacitor C7 is grounded, the positive electrode of the capacitor C7 is connected to one end of the resistor R17, the positive input end of the first comparator, the positive input end of the second comparator and the positive input end of the voltage follower module, the other end of the resistor R17 is connected to one end of the resistor R18, the other end of the resistor R18 is connected to the negative electrode of the diode D5 and one end of the resistor R19, and the other end of the resistor R19 is connected to the DIM interface.

[0011] Among them, the turnable three-in-one dimming circuit also includes a diode D4 and a Zener diode ZD1, the anode of the diode D4 is connected to the positive input end of the voltage follower module and one end of the resistor R17, the cathode of the diode D4 is connected to the input end of the Zener diode ZD1, and the output end of the Zener diode ZD1 is grounded GND.

[0012] The voltage source generating module includes a third comparator, a resistor R15, a resistor R16, a resistor R14, a resistor R13, a resistor R11, a resistor R12, a three-terminal adjustable shunt reference source V1 and a capacitor C5, one end of the resistor R11 is connected to the input power supply, the other end of the resistor R11 is connected to one end of the resistor R12 and the reference electrode of the three-terminal adjustable shunt reference source V1, the other end of the resistor R12 is connected to the positive input end of the third comparator, the positive input end of the third comparator is also connected to one end of the resistor R15, the other end of the resistor R15 is connected to one end of the resistor R16 and the positive electrode of the diode D5, the other end of the resistor R16 is connected to one end of the resistor R14 and the output end of the third comparator, the other end of the resistor R14 is connected to one end of the resistor R13 and the negative input end of the third comparator, the other end of the resistor R13 is grounded GND, the anode of the three-terminal adjustable shunt reference source V1 is grounded GND, and the cathode of the three-terminal adjustable shunt reference source V1 is connected to the ground GND through the capacitor C5. The reference electrode of the three-terminal adjustable shunt reference source V1 is also connected to the cathode of the three-terminal adjustable shunt reference source V1, and the reference electrode of the three-terminal adjustable shunt reference source V1 is connected to the negative input terminal of the first comparator and the negative input terminal of the second comparator after voltage division by resistors R9 and R10.

[0013] Among them, the voltage follower module includes a diode D3 and a fourth comparator, the cathode of the diode D3 is connected to the REF interface, the anode of the diode D3 is connected to the output end of the fourth comparator, the positive input end of the fourth comparator is connected to the first output end of the RC filter module, and the negative input end of the fourth comparator is connected to the cathode of the diode D3.

[0014] Among them, the first comparator module also includes a resistor R2, a resistor R5, a resistor R6, a resistor R3 and a capacitor C1, one end of the resistor R2 is connected to the MOS interface, the other end of the resistor R2 is connected to the negative electrode of the capacitor C1 and the output end of the first comparator, the positive input end of the first comparator is connected to one end of the resistor R5, the other end of the resistor R5 is connected to the positive electrode of the capacitor C7, the positive electrode of the capacitor C1 is connected to one end of the resistor R3, the other end of the resistor R3 is connected to the negative input end of the first comparator and one end of the resistor R6, and the other end of the resistor R6 is connected to one end of the resistor R9 and one end of the resistor R10.

[0015] Among them, the second comparator module also includes a diode D1, a resistor R7, a resistor R8, a resistor R4 and a capacitor C2, the cathode of the diode D1 is connected to the OPTO interface, the anode of the diode D1 is connected to the cathode of the capacitor C2 and the output end of the second comparator, the positive input end of the second comparator is connected to one end of the resistor R7, the other end of the resistor R7 is connected to the positive electrode of the capacitor C7, the positive electrode of the capacitor C2 is connected to one end of the resistor R4, the other end of the resistor R4 is connected to the negative input end of the second comparator and one end of the resistor R8, and the other end of the resistor R8 is connected to one end of the resistor R9 and one end of the resistor R10.

[0016] Beneficial effects of the present invention: The present invention comprises a linearly adjustable input voltage source, a voltage source generating module, an RC filter module, a voltage follower module and a first comparator module. The input voltage source is connected to the input end of the voltage source generating module, the second output end of the voltage source generating module is connected to the first input end of the RC filter module through a diode D5, the first output end of the RC filter module is connected to the positive input end of the voltage follower module, the output end of the voltage follower module is connected to a REF interface, the REF interface is connected to a lamp, and the second input end of the RC filter module is also connected to a DIM interface;

[0017] The DIM interface receives an external dimming signal between the DIM interface and the ground GND, and the external dimming signal includes a PWM signal, a 0-10V voltage signal, and an adjustable resistance voltage signal; the first comparator module includes a first comparator, the positive input end of the first comparator is connected to the second output end of the RC filter module, the negative input end of the first comparator provides a reference voltage, the first output end of the voltage source generation module is connected to the negative input end of the first comparator after voltage division by resistors R9 and R10, the output end of the first comparator is connected to the MOS interface, and the MOS interface is connected to the lamp. The present invention receives three external dimming signals and can be turned off by adding an RC filter module and a first comparator, thereby realizing a turnable three-in-one dimming. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The invention is further described using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the invention. A person skilled in the art can obtain other drawings based on the following drawings without creative work.

[0019] Figure 1 The invention discloses a circuit diagram of a switchable three-in-one dimming circuit. DETAILED DESCRIPTION

[0020] The present invention is further described in conjunction with the following examples.

[0021] A three-in-one dimming circuit that can be turned off in this embodiment is used to dim and turn off a lamp. Figure 1 As shown, it includes a linearly adjustable input voltage source, a voltage source generating module M1, an RC filtering module M2, a voltage follower module M3 and a first comparator module M4;

[0022] The input voltage source is connected to the input terminal IN1 of the voltage source generating module M1, the second output terminal OUT101 of the voltage source generating module M1 is connected to the first input terminal IN2 of the RC filtering module M2 through a diode D5, the first output terminal OUT2 of the RC filtering module M2 is connected to the positive input terminal IN3 of the voltage follower module M3, the output terminal OUT3 of the voltage follower module M3 is connected to the REF interface, the REF interface is connected to the lamp, and the second input terminal IN202 of the RC filtering module M2 is connected to the DIM interface;

[0023] The DIM interface receives an external dimming signal between the ground GND, and the external dimming signal includes a PWM signal, a 0-10V voltage signal and an adjustable resistor voltage signal, wherein the RC filter module M2 can adjust the PWM digital signal to an analog signal (the 0-10V voltage signal and the adjustable resistor voltage signal are analog signals themselves) and input it to the positive input terminal 3 of the voltage follower module M3.

[0024] The first comparator module M4 includes a first comparator 100, a positive input terminal 10 of the first comparator 100 is connected to the second output terminal OUT202 of the RC filter module M2, a negative input terminal 9 of the first comparator 100 provides a reference voltage, a first output terminal OUT1 of the voltage source generating module M1 is connected to the negative input terminal 9 of the first comparator 100 after voltage division by resistors R9 and R10, an output terminal 8 of the first comparator 100 is connected to a MOS interface, and the MOS interface is connected to a lamp.

[0025] The dimming circuit of this embodiment is compatible with three dimming signals: PWM signal, 0-10V voltage signal and adjustable voltage signal, realizing three-in-one dimming technology, and comparing the reference voltage and the voltage of the dimming signal through the first comparator module M4, so as to realize the function of freely shutting down the lamp.

[0026] Among them, the switchable three-in-one dimming circuit also includes a second comparator module M5, the second comparator module M5 includes a second comparator 200, the positive input terminal 12 of the second comparator 200 is connected to the second output terminal OUT202 of the RC filter module M2, the negative input terminal 13 of the second comparator 200 provides a reference voltage, the first output terminal OUT1 of the voltage source generating module M1 is connected to the negative input terminal 13 of the second comparator 200 after voltage division by resistors R9 and R10, and the output terminal 14 of the second comparator 200 is connected to the lamp through an optocoupler.

[0027] By comparing the reference voltage of the second comparator with the voltage of the dimming signal, when the input voltage is less than the reference voltage of 0.55 volts, the second comparator outputs a low level to the optocoupler, which can lower the voltage of the optocoupler (for example, if it was originally 48 volts, it can be lowered to 40 volts) to reduce standby power consumption.

[0028] Among them, the RC filter module M2 includes a capacitor C7, a resistor R17, a resistor R18 and a resistor R19, the negative electrode of the capacitor C7 is grounded, the positive electrode of the capacitor C7 is connected to one end of the resistor R17 and the positive input terminal IN3 of the voltage follower module M3, the other end of the resistor R17 is connected to one end of the resistor R18, the other end of the resistor R18 is connected to the negative electrode of the diode D5 and one end of the resistor R19, and the other end of the resistor R19 is connected to the DIM interface.

[0029] By filtering through the RC filter module M2, the PWM digital signal can be adjusted to an analog signal and input to the input end of the voltage follower module.

[0030] The switchable three-in-one dimming circuit further includes a diode D4 and a Zener diode ZD1, wherein the anode of the diode D4 is connected to the positive input terminal IN3 of the voltage follower module M3, the cathode of the diode D4 is connected to the input terminal of the Zener diode ZD1, and the output terminal of the Zener diode ZD1 is grounded GND.

[0031] The connection of diode D4 can prevent the DIM interface and GND from being connected reversely.

[0032] The voltage source generating module M1 includes a third comparator 300, a resistor R15, a resistor R16, a resistor R14, a resistor R13, a resistor R11, a resistor R12, a three-terminal adjustable shunt reference source V1 and a capacitor C5, one end of the resistor R11 is connected to the input voltage source, the other end of the resistor R11 is connected to one end of the resistor R12 and a reference electrode 23 of the three-terminal adjustable shunt reference source V1, the reference electrode 23 provides a voltage of 2.5V to the positive input terminal 5 of the third comparator 300 through the resistor R12, and the third comparator The positive input terminal 5 of the comparator 300 is also connected to one end of a resistor R15, the other end of the resistor R15 is connected to one end of a resistor R16 and the positive electrode of a diode D5, the other end of the resistor R16 is connected to one end of a resistor R14, the other end of the resistor R14 is connected to one end of a resistor R13 and the negative input terminal of the voltage source generator, the other end of the resistor R13 is grounded GND, the anode 22 of the three-terminal adjustable shunt reference source V1 is grounded GND, the cathode 21 of the three-terminal adjustable shunt reference source V1 is connected to the ground GND through a capacitor C5, the reference electrode 23 of the three-terminal adjustable shunt reference source V1 is connected to the cathode 21 of the three-terminal adjustable shunt reference source V1, and the three-terminal adjustable shunt reference source V1 is also connected to the negative input terminal 9 of the first comparator module M4 through resistors R9 and R10.

[0033] The voltage source generating module M1 is a bidirectional amplifier circuit, which provides a voltage of 2.5V through a three-terminal adjustable shunt reference source V1. Since resistors R15, R16, R14, R13 and ground form a loop, diode D5 is connected in the loop, and the voltage change of DIM is fed back to the loop, the voltages of the three feet of the voltage source generating module can be basically consistent, thereby maintaining the stability of the input signal and removing power supply clutter and interference.

[0034] Among them, the voltage follower module M3 includes a diode D3 and a fourth comparator 400, the cathode of the diode D3 is connected to the REF interface, the anode of the diode D3 is connected to the output terminal 1 of the fourth comparator 400, the positive input terminal 3 of the fourth comparator 400 is connected to the first output terminal OUT2 of the RC filter module M2, and the negative input terminal 2 of the fourth comparator 400 is connected to the cathode of the diode D3.

[0035] Among them, the first comparator module M4 also includes a resistor R2, a resistor R5, a resistor R6, a resistor R3 and a capacitor C1, one end of the resistor R2 is connected to the MOS interface, the other end of the resistor R2 is connected to the negative electrode of the capacitor C1 and the output end 8 of the first comparator 100, the positive input end 10 of the first comparator 100 is connected to one end of the resistor R5, the other end of the resistor R5 is connected to the second output end OUT202 of the RC filter module M2, the positive electrode of the capacitor C1 is connected to one end of the resistor R3, the other end of the resistor R3 is connected to the negative input end 9 of the first comparator 100 and one end of the resistor R6, and the other end of the resistor R6 is connected to the first output end OUT1 of the voltage source generating module M1 through the resistor R9 and the resistor R10.

[0036] The 2.5V voltage provided by the voltage source generating module M1 is divided by resistors R9 and R10 to provide a 0.55V voltage to the negative input terminal 9 of the first comparator 100 as a reference voltage. The positive input terminal 10 of the first comparator 100 receives the input voltage of the RC filtering module M2, and compares the reference voltage with the input voltage. When the input voltage is less than 0.55V, the first comparator 100 outputs a low level to the MOS tube to turn off the MOS tube, thereby realizing the power supply judgment.

[0037] Among them, the second comparator module M5 also includes a diode D1, a resistor R7, a resistor R8, a resistor R4 and a capacitor C2, the cathode of the diode D1 is connected to the optocoupler, the anode of the diode D1 is connected to the cathode of the capacitor C2 and the output terminal 14 of the second comparator, the positive input terminal 12 of the second comparator is connected to one end of the resistor R7, the other end of the resistor R7 is connected to the second output terminal OUT202 of the RC filter module M2, the positive electrode of the capacitor C2 is connected to one end of the resistor R4, the other end of the resistor R4 is connected to the negative input terminal 13 of the second comparator 200 and one end of the resistor R8, and the other end of the resistor R8 is connected to the first output terminal OUT1 of the voltage source generating module M1 through the resistors R9 and R10.

[0038] The 2.5V voltage provided by the voltage source generating module M1 is divided by the resistors R9 and R10 to provide a 0.55V voltage to the negative input terminal 13 of the second comparator 200 as a reference voltage. The positive input terminal 12 of the second comparator 200 receives the input voltage of the RC filter module M2, and compares the reference voltage with the input voltage. When the input voltage is lower than 0.55V, the second comparator 200 outputs a low level to the optocoupler to lower the voltage of the optocoupler. For example, the original voltage of 48V can be pulled down to 40V to reduce standby power consumption.

[0039] In this embodiment, one of the three dimming signals is input between the DIM interface and GND, and is sent to the positive input terminal 10 of the first comparator 100 through the RC filter module M2, and is compared with the reference voltage of the negative input terminal 9 of the first comparator 100. When the input voltage is less than the reference voltage, the first comparator 100 outputs a low level to the MOS tube to turn off the MOS tube, thereby realizing the two major functions of turning off the lamp and three-in-one dimming.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A three-in-one dimming circuit that can be turned off, used to dim and turn off a lamp, characterized in that: It includes a linearly adjustable input voltage source, a voltage source generating module, an RC filtering module, a voltage follower module and a first comparator module; The input voltage source is connected to the input end of the voltage source generating module, the second output end of the voltage source generating module is connected to the first input end of the RC filter module through a diode D5, the first output end of the RC filter module is connected to the positive input end of the voltage follower module, the output end of the voltage follower module is connected to the REF interface, the REF interface is connected to the lamp, and the second input end of the RC filter module is connected to the DIM interface; An external dimming signal is received between the DIM interface and the ground GND, and the external dimming signal includes a PWM signal, a 0-10V voltage signal and an adjustable resistance voltage signal; The first comparator module includes a first comparator, the positive input end of the first comparator is connected to the second output end of the RC filter module, the negative input end of the first comparator provides a reference voltage, the first output end of the voltage source generating module is connected to the negative input end of the first comparator after voltage division by resistors R9 and R10, the output end of the first comparator is connected to the MOS interface, and the MOS interface is connected to the lamp; The voltage source generating module comprises a third comparator, a resistor R15, a resistor R16, a resistor R14, a resistor R13, a resistor R11, a resistor R12, a three-terminal adjustable shunt reference source V1 and a capacitor C5, one end of the resistor R11 is connected to the input power supply, the other end of the resistor R11 is connected to one end of the resistor R12 and the reference electrode of the three-terminal adjustable shunt reference source V1, the other end of the resistor R12 is connected to the positive input end of the third comparator, the positive input end of the third comparator is also connected to one end of the resistor R15, the other end of the resistor R15 is connected to one end of the resistor R16 and the positive electrode of the diode D5, the other end of the resistor R16 is connected to the positive electrode of the diode D5, and the other end of the resistor R16 is connected to the positive electrode of the diode D5. The first terminal of the three-terminal adjustable shunt reference source V1 is connected to one end of the resistor R14 and the output end of the third comparator, the other end of the resistor R14 is connected to one end of the resistor R13 and the negative input end of the third comparator, the other end of the resistor R13 is grounded GND, the anode of the three-terminal adjustable shunt reference source V1 is grounded GND, the cathode of the three-terminal adjustable shunt reference source V1 is connected to the ground GND through the capacitor C5, the reference electrode of the three-terminal adjustable shunt reference source V1 is also connected to the cathode of the three-terminal adjustable shunt reference source V1, and the reference electrode of the three-terminal adjustable shunt reference source V1 is connected to the negative input end of the first comparator and the negative input end of the second comparator after voltage division by the resistors R9 and R10; The voltage follower module includes a diode D3 and a fourth comparator, the cathode of the diode D3 is connected to the REF interface, the anode of the diode D3 is connected to the output end of the fourth comparator, the positive input end of the fourth comparator is connected to the first output end of the RC filter module, and the negative input end of the fourth comparator is connected to the cathode of the diode D3; The first comparator module also includes a resistor R2, a resistor R5, a resistor R6, a resistor R3 and a capacitor C1, one end of the resistor R2 is connected to the MOS interface, the other end of the resistor R2 is connected to the negative electrode of the capacitor C1 and the output end of the first comparator, the positive input end of the first comparator is connected to one end of the resistor R5, the other end of the resistor R5 is connected to the positive electrode of the capacitor C7, the positive electrode of the capacitor C1 is connected to one end of the resistor R3, the other end of the resistor R3 is connected to the negative input end of the first comparator and one end of the resistor R6, and the other end of the resistor R6 is connected to one end of the resistor R9 and one end of the resistor R10.

2. The switchable three-in-one dimming circuit according to claim 1, characterized in that: It also includes a second comparator module, which includes a second comparator, wherein the positive input terminal of the second comparator is connected to the second output terminal of the RC filter module, the negative input terminal of the second comparator provides a reference voltage, the first output terminal of the voltage source generating module is connected to the negative input terminal of the second comparator after voltage division by resistors R9 and R10, and the output terminal of the second comparator is connected to the OPTO interface, which is connected to the lamp via an optical coupling.

3. The switchable three-in-one dimming circuit according to claim 2, characterized in that: The RC filter module includes a capacitor C7, a resistor R17, a resistor R18 and a resistor R19. The negative electrode of the capacitor C7 is grounded, the positive electrode of the capacitor C7 is connected to one end of the resistor R17, the positive input end of the first comparator, the positive input end of the second comparator and the positive input end of the voltage follower module, the other end of the resistor R17 is connected to one end of the resistor R18, the other end of the resistor R18 is connected to the negative electrode of the diode D5 and one end of the resistor R19, and the other end of the resistor R19 is connected to the DIM interface.

4. The switchable three-in-one dimming circuit according to claim 3, characterized in that: The switchable three-in-one dimming circuit also includes a diode D4 and a voltage-stabilizing diode ZD1. The anode of the diode D4 is connected to the positive input terminal of the voltage follower module and one end of the resistor R17. The cathode of the diode D4 is connected to the input terminal of the voltage-stabilizing diode ZD1. The output terminal of the voltage-stabilizing diode ZD1 is grounded GND.

5. The switchable three-in-one dimming circuit according to claim 3, characterized in that: The second comparator module also includes a diode D1, a resistor R7, a resistor R8, a resistor R4 and a capacitor C2, the cathode of the diode D1 is connected to the OPTO interface, the anode of the diode D1 is connected to the cathode of the capacitor C2 and the output end of the second comparator, the positive input end of the second comparator is connected to one end of the resistor R7, the other end of the resistor R7 is connected to the positive electrode of the capacitor C7, the positive electrode of the capacitor C2 is connected to one end of the resistor R4, the other end of the resistor R4 is connected to the negative input end of the second comparator and one end of the resistor R8, and the other end of the resistor R8 is connected to one end of the resistor R9 and one end of the resistor R10.

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