Stepless dimming circuit

Abstract

The utility model discloses a stepless dimming circuit, which comprises a main control module, a rheostat ZNR, a sampling module and a pull rope switch, the input end of the rheostat ZNR is connected with an external power supply, one output end of the rheostat ZNR is electrically connected with one end of the sampling module, the sampling module is used for sampling electric signals of the rheostat ZNR, and the pull rope switch is connected with the rheostat ZNR. The other end of the sampling module is electrically connected with the main control module so as to feed back the electric signal to the main control module, and the pull rope switch is electrically connected with the input end of the main control module; when the pull rope switch is switched on or switched off, the rheostat ZNR performs smooth resistance changing, the sampling module samples changed electric signals of the rheostat ZNR, and the control module outputs stepless dimming signals according to the changed electric signals so as to control an LED load.

Description

Technical Field

[0001] The utility model relates to the technical field of LED dimming circuits, in particular to a stepless dimming circuit. Background Art

[0002] Stepless dimming can be simply understood as the brightness of the lamp can change smoothly, and can be adjusted from 1% to 100% brightness, and there is no factory preset brightness limit. For example: traditional lamps are divided into several levels, some have only one brightness, and some have several brightness levels, but the brightness of the lamp must be controlled by a switch to set its brightness level. With stepless dimming lamps, users can choose their own comfortable brightness according to their different environmental needs. For example, when the brightness of the light is not high at night, a very low brightness can be set to achieve comfort. It can also extend the continuous use time of the lamp. The existing stepless dimming circuit is generally implemented by a key switch or a touch switch. The key switch requires the user to press repeatedly, which is not convenient to use. The touch switch requires a special touch control chip, which is costly. Utility Model Content

[0003] The purpose of the utility model is to solve at least one of the technical problems existing in the prior art and to provide a stepless dimming circuit which is simple in structure, low in cost and easy to use.

[0004] According to the embodiment of the utility model, the stepless dimming circuit includes a main control module, a rheostat ZNR, a sampling module and a pull-string switch, the input end of the rheostat ZNR is connected to an external power supply, an output end of the rheostat ZNR is electrically connected to one end of the sampling module, the sampling module is used to sample the electrical signal of the rheostat ZNR, the other end of the sampling module is electrically connected to the main control module to feed the electrical signal back to the main control module, and the pull-string switch is electrically connected to the input end of the main control module; when the pull-string switch is closed, the rheostat ZNR performs smooth resistance change, the sampling module samples the changing electrical signal of the rheostat ZNR, and the control module outputs a stepless dimming signal according to the changing electrical signal to control the LED load.

[0005] According to some embodiments of the present invention, a step-down module is also included, which includes a capacitor CX2, a resistor R3 and a resistor R4, one end of the capacitor CX2 is electrically connected to the variable resistor ZNR and one end of the resistor R3 respectively, the other end of the resistor R3 is electrically connected to one end of the resistor R4, and the other end of the resistor R4 is electrically connected to the other end of the capacitor CX2.

[0006] According to some embodiments of the utility model, a rectifier module is further included, wherein the rectifier module includes a diode D1 and a zener diode ZD1, wherein the cathode of the diode D1 is electrically connected to the anode of the zener diode ZD1 and the other end of the capacitor CX2, respectively, the anode of the diode D1 is grounded, the cathode of the zener diode ZD1 is electrically connected to the other output end of the variable resistor ZNR and outputs a working voltage V1 to power the main control module.

[0007] According to some embodiments of the present invention, a first filtering module is further included. The first filtering module includes a capacitor CX1 and a resistor R1 connected in parallel with each other. The first filtering module is connected in parallel with the variable resistor ZNR.

[0008] According to some embodiments of the present invention, a second filtering module is further included, which includes a capacitor C1 and a resistor R6 connected in parallel, one end of the second filtering module is electrically connected to the anode of the diode D1, and the other end of the second filtering module is electrically connected to the cathode of the Zener diode ZD1.

[0009] According to some embodiments of the utility model, a driving module is also included, the driving module includes a triac Q1, a resistor R7, a resistor RT, and a capacitor CT, one end of the triac Q1 and one end of the resistor RT are respectively input with the working voltage V1, the other end of the resistor RT is electrically connected to one end of the capacitor CT, the other end of the capacitor CT and the other end of the triac Q1 are respectively electrically connected to the LED load, and the third end of the triac Q1 is electrically connected to the main control module via the series resistor R7.

[0010] According to some embodiments of the present utility model, the sampling module includes a resistor R5 and a capacitor C2, one end of the resistor R5 and one end of the capacitor C2 are respectively electrically connected to the main control module, the other end of the capacitor C2 is grounded, and the other end of the resistor R5 is respectively electrically connected to the other end of the resistor R3 and one end of the resistor R4.

[0011] According to some embodiments of the present invention, the main control module adopts a FT61EC21A chip.

[0012] The stepless dimming circuit according to the embodiment of the utility model has at least the following beneficial effects: when the pull-cord switch is closed, the control module gives a working signal to make the variable resistor ZNR change resistance smoothly, the sampling module samples the changing electrical signal of the variable resistor ZNR, and the control module outputs a stepless dimming signal according to the changing electrical signal to control the LED load. Since a pull-cord switch is used, the circuit starts to work as long as the pull-cord switch is pulled to keep the switch closed or open. When the brightness of the LED load is adjusted to the desired effect, the pull-cord switch can be released. The operation is easy, the structure is simple, and the cost is low.

[0013] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The specific implementation of the utility model is further described below in conjunction with the accompanying drawings;

[0015] Figure 1 It is the structural block diagram of the stepless dimming circuit;

[0016] Figure 2 It is the circuit schematic diagram of the stepless dimming circuit. DETAILED DESCRIPTION

[0017] This section will describe in detail the specific embodiments of the utility model. The preferred embodiments of the utility model are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the utility model, but it cannot be understood as a limitation on the protection scope of the utility model.

[0018] In the description of the present invention, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0019] In the description of the present utility model, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0020] Reference Figure 1 to Figure 2The utility model discloses a stepless dimming circuit, comprising a main control module 10, a rheostat ZNR, a sampling module 20 and a pull-rope switch K1. The input end of the rheostat ZNR is connected to an external power supply, an output end of the rheostat ZNR is electrically connected to one end of the sampling module 20, the sampling module 20 is used to sample the electrical signal of the rheostat ZNR, the other end of the sampling module 20 is electrically connected to the main control module 10 to feed back the electrical signal to the main control module 10, and the pull-rope switch K1 is electrically connected to the input end of the main control module 10; when the pull-rope switch K1 is closed, the rheostat ZNR smoothly changes resistance, the sampling module 20 samples the changing electrical signal of the rheostat ZNR, and the control module outputs a stepless dimming signal according to the changing electrical signal to control the LED load. Since the pull-rope switch K1 is used, as long as the pull-rope switch K1 is pulled to keep closed or disconnected, the circuit starts to work. When the brightness of the LED load is adjusted to the desired effect, the pull-rope switch K1 can be released. The pull rope can be a bead chain, which is easy to operate, simple in structure and low in cost.

[0021] like Figure 2 The main control module 10 adopts the FT61EC21A chip, and the sampling module 20 includes a resistor R5 and a capacitor C2. One end of the resistor R5 and one end of the capacitor C2 are electrically connected to the input end of the FT61EC21A chip respectively, and the other end of the capacitor C2 is grounded. The other end of the resistor R5 is electrically connected to the other end of the resistor R3 and one end of the resistor R4 respectively. The electrical signal of the variable resistor ZNR is sampled through the resistor R5, and the capacitor C2 has a filtering effect.

[0022] It also includes a step-down module 30, a rectifier module 40 and a drive module 50. The step-down module 30 includes a capacitor CX2, a resistor R3 and a resistor R4. One end of the capacitor CX2 is electrically connected to the variable resistor ZNR and one end of the resistor R3 respectively. The other end of the resistor R3 is electrically connected to one end of the resistor R4. The other end of the resistor R4 is electrically connected to the other end of the capacitor CX2 to step down the external power supply connected to the input end of the variable resistor ZNR. The rectifier module 40 includes a diode D1 and a voltage regulator diode ZD1. The cathode of the diode D1 is electrically connected to the anode of the voltage regulator diode ZD1 and the other end of the capacitor CX2 respectively. The anode of the diode D1 is grounded. The cathode of the voltage regulator diode ZD1 is electrically connected to the other output end of the variable resistor ZNR and outputs the rectified working voltage V1 to power the FT61EC21A chip and the drive module 50. The driving module 50 includes a triac Q1, a resistor R7, a resistor RT, and a capacitor CT. One end of the triac Q1 and one end of the resistor RT are respectively input with a working voltage V1, the other end of the resistor RT is electrically connected to one end of the capacitor CT, the other end of the capacitor CT and the other end of the triac Q1 are respectively electrically connected to the LED load, and the third end of the triac Q1 is electrically connected to the signal end of the FT61EC21A chip via the series resistor R7. The FT61EC21A chip outputs a stepless dimming signal to the driving module 50 according to the changing electrical signal on the variable resistor ZNR to control the LED load to achieve stepless dimming.

[0023] In some embodiments, a first filter module 61 and a second filter module 62 are further included. The first filter module 61 includes a capacitor CX1 and a resistor R1 connected in parallel with each other. The first filter module 61 is connected in parallel with the variable resistor ZNR to filter the electrical signal at the input end. The second filter module 62 includes a capacitor C1 and a resistor R6 connected in parallel with each other. One end of the second filter module 62 is electrically connected to the anode of the diode D1, and the other end of the second filter module 62 is electrically connected to the cathode of the voltage stabilizing diode ZD1 to filter the electrical signal at the output end of the working voltage V1 to ensure the output of a good working voltage.

[0024] It is easy for those skilled in the art to understand that the above preferred embodiments can be freely combined and superimposed without conflict.

[0025] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention specification and drawings under the utility model concept, or directly or indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A stepless dimming circuit, characterized in that: include: A main control module (10), a rheostat ZNR, a sampling module (20) and a pull-wire switch K1, wherein the input end of the rheostat ZNR is connected to an external power supply, an output end of the rheostat ZNR is electrically connected to one end of the sampling module (20), the sampling module (20) is used to sample an electrical signal of the rheostat ZNR, the other end of the sampling module (20) is electrically connected to the main control module (10) to feed back the electrical signal to the main control module (10), and the pull-wire switch K1 is electrically connected to the input end of the main control module (10); when the pull-wire switch K1 is closed, the rheostat ZNR performs smooth resistance change, the sampling module (20) samples the changing electrical signal of the rheostat ZNR, and the main control module outputs a stepless dimming signal according to the changing electrical signal to control an LED load.

2. The stepless dimming circuit according to claim 1, characterized in that: The invention also comprises a step-down module (30), wherein the step-down module (30) comprises a capacitor CX2, a resistor R3 and a resistor R4, wherein one end of the capacitor CX2 is electrically connected to the variable resistor ZNR and one end of the resistor R3 respectively, the other end of the resistor R3 is electrically connected to one end of the resistor R4, and the other end of the resistor R4 is electrically connected to the other end of the capacitor CX2.

3. The stepless dimming circuit according to claim 2, characterized in that: It also includes a rectifier module (40), the rectifier module (40) including a diode D1 and a voltage regulator diode ZD1, the cathode of the diode D1 being electrically connected to the anode of the voltage regulator diode ZD1 and the other end of the capacitor CX2 respectively, the anode of the diode D1 being grounded, the cathode of the voltage regulator diode ZD1 being electrically connected to the other output end of the resistor ZNR and outputting a working voltage V1 to supply power to the main control module (10).

4. The stepless dimming circuit according to claim 3, characterized in that: It also comprises a first filtering module (61), wherein the first filtering module (61) comprises a capacitor CX1 and a resistor R1 connected in parallel with each other, and the first filtering module (61) is connected in parallel with the variable resistor ZNR.

5. The stepless dimming circuit according to claim 4, characterized in that: The invention also comprises a second filter module (62), wherein the second filter module (62) comprises a capacitor C1 and a resistor R6 connected in parallel with each other, one end of the second filter module (62) is electrically connected to the anode of the diode D1, and the other end of the second filter module (62) is electrically connected to the cathode of the voltage stabilizing diode ZD1.

6. The stepless dimming circuit according to claim 5, characterized in that: The device also comprises a driving module (50), wherein the driving module (50) comprises a triac Q1, a resistor R7, a resistor RT, and a capacitor CT, wherein one end of the triac Q1 and one end of the resistor RT are respectively input with the working voltage V1, the other end of the resistor RT is electrically connected to one end of the capacitor CT, the other end of the capacitor CT and the other end of the triac Q1 are respectively electrically connected to the LED load, and the third end of the triac Q1 is electrically connected to the main control module (10) via the series resistor R7.

7. The stepless dimming circuit according to claim 2, characterized in that: The sampling module (20) comprises a resistor R5 and a capacitor C2, one end of the resistor R5 and one end of the capacitor C2 are respectively electrically connected to the main control module (10), the other end of the capacitor C2 is grounded, and the other end of the resistor R5 is respectively electrically connected to the other end of the resistor R3 and one end of the resistor R4.

8. The stepless dimming circuit according to claim 1, characterized in that: The main control module (10) adopts the FT61EC21A chip.

9. The stepless dimming circuit according to claim 1, characterized in that: The pull rope on the pull rope switch K1 adopts a bead chain.

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