LED drive circuit and direct type panel lamp

Abstract

The utility model discloses an LED driving circuit and a direct type panel lamp, the LED driving circuit is used for providing direct current for LED lamp beads, the LED driving circuit comprises a rectification unit, a filtering unit and a constant current unit, the LED lamp beads are connected in series between the filtering unit and the constant current unit, the constant current unit is used for outputting stable current to the LED lamp beads, and the filtering unit is used for filtering the stable current. The LED driving circuit is provided with a constant current output end, a current adjusting end and a grounding end, the constant current output end is connected with the LED lamp beads in series, the current adjusting end is grounded through an adjusting resistor, and the LED driving circuit further comprises a voltage dividing element connected with the LED lamp beads in series. The voltage dividing element is connected with the LED lamp bead in series, the voltage of the constant current unit can be reduced, and the problem that the LED driving circuit is damaged due to overheating is avoided.

Description

Technical Field

[0001] The present application relates to the field of panel lights, and in particular to an LED driving circuit and a direct-down panel light. Background Art

[0002] LED panel lights have the advantages of good illumination uniformity, soft and comfortable light, environmentally friendly materials, and low power consumption. They are currently a popular indoor lighting fixture. They usually include a lamp body and an LED driver power supply. A light-emitting component is installed in the lamp body. The light-emitting component includes a substrate and LED lamp beads arranged on the substrate. The LED driver power supply is used to drive the LED lamp beads to work normally.

[0003] LED driver power supplies generally include a rectifier unit, a filter unit, and a constant current unit. However, some constant current units have strict voltage requirements. In order to prevent the voltage of the constant current unit from being too high and damaging the circuit, the LED driver power supply needs to be further improved. Utility Model Content

[0004] The utility model provides an LED driving circuit and a direct-down panel lamp, which solves the problem of excessively high voltage of the constant current unit in the prior art.

[0005] An LED driving circuit, used for providing direct current to LED lamp beads, comprises a rectifying unit, a filtering unit and a constant current unit, characterized in that the LED lamp beads are connected in series between the filtering unit and the constant current unit, the constant current unit is used for outputting a stable current to the LED lamp beads, and has a constant current output end, a current regulating end and a grounding end, the constant current output end is connected in series with the LED lamp beads, the current regulating end is grounded through an adjusting resistor, and the LED driving circuit also comprises a voltage divider element connected in series with the LED lamp beads.

[0006] Several optional methods are also provided below, but they are not intended to be additional limitations on the above-mentioned overall solution, but are merely further supplements or preferences. Under the premise that there are no technical or logical contradictions, each optional method can be combined with the above-mentioned overall solution separately, and multiple optional methods can also be combined.

[0007] Optionally, the voltage dividing element is a resistor.

[0008] Optionally, the filtering unit includes a voltage stabilizing diode RV1, a capacitor CD1, a capacitor CD2 and a resistor R1 connected in parallel.

[0009] Optionally, the constant current units are multiple and arranged in parallel.

[0010] The present application also provides a direct-down panel lamp, comprising a back plate, a diffusion plate, a frame, a light-emitting component and the above-mentioned LED driving circuit, wherein the back plate is arranged opposite to the diffusion plate, the frame is a frame structure formed by connecting a plurality of frame strips, the edges of the back plate and the diffusion plate are fixed to the frame, the light-emitting component comprises a substrate and LED lamp beads arranged on the substrate, the substrate is fixed on the back plate and arranged toward the diffusion plate.

[0011] Optionally, the substrate is a plurality of strips arranged in parallel, the LED lamp beads on the same substrate are arranged along the length direction thereof, and the voltage divider element is arranged between two adjacent LED lamp beads.

[0012] Optionally, two groups of LED lamp beads are arranged on each substrate, and the LED lamp beads in the same group are arranged in series, and the two groups of LED lamp beads are arranged in parallel, respectively on the left and right sections of the substrate.

[0013] Optionally, the LED lamp bead is covered with a lens.

[0014] The LED driving circuit and direct-down panel lamp of the present application have at least the following technical effects:

[0015] In the present application, the voltage divider element is connected in series with the LED lamp bead, which can reduce the voltage of the constant current unit and avoid the problem of damage to the LED driving circuit caused by overheating. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the module structure of an LED driving circuit according to an embodiment of the present application;

[0017] Figure 2 A circuit schematic diagram of an LED driving circuit according to an embodiment of the present application;

[0018] Figure 3 A schematic diagram of the structure of a direct-down panel light according to an embodiment of the present application;

[0019] Figure 4 is a schematic diagram of the structure of a light-emitting component;

[0020] Figure 5 It is a schematic diagram of the structure of the light bar;

[0021] Figure 6 for Figure 4 A partial cross-sectional view of .

[0022] The reference numerals in the figures are described as follows:

[0023] 10. Rectification unit; 20. Filter unit; 30. Constant current unit; 31. Adjustment resistor;

[0024] 100, back plate; 101, first side surface; 102, second side surface; 110, bottom wall; 120, side wall;

[0025] 200, light emitting component; 210, light bar; 220, substrate; 231, LED lamp bead; 231a, LED lamp bead; 231b, LED lamp bead; 232, lens; 240, voltage divider element; 250, wire;

[0026] 300, diffusion plate;

[0027] 400, frame; 410, frame strip; 411, first mounting surface; 412, second mounting surface. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0029] It should be noted that when a component is referred to as being "connected" to another component, it may be directly connected to the other component or there may be a central component. When a component is referred to as being "disposed on" another component, it may be directly disposed on the other component or there may be a central component at the same time.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0031] See also Figure 1 , Figure 2 and Figure 5An embodiment of the present application provides an LED driving circuit for providing direct current to an LED lamp bead 231, including a rectifying unit 10, a filtering unit 20 and a constant current unit 30. Some existing constant current units 30 have strict requirements on voltage. In order to avoid excessive voltage from damaging the circuit, in the LED driving circuit of the present application, the LED lamp bead 231 is connected in series between the filtering unit 20 and the constant current unit 30. The constant current unit 30 is used to output a stable current to the LED lamp bead 231, and has a constant current output terminal OUT, a current regulating terminal REXT and a ground terminal GND. The constant current output terminal OUT is connected in series with the LED lamp bead 231, and the current regulating terminal REXT is grounded through an adjusting resistor 31. The LED driving circuit also includes a voltage divider element 240 connected in series with the LED lamp bead 231.

[0032] In the present application, the voltage divider element 240 is connected in series with the LED lamp bead 231 to reduce the voltage of the constant current unit 30 and avoid the problem of damage to the LED driving circuit caused by overheating.

[0033] In this embodiment, preferably, the voltage dividing element 240 is a resistor, and the specific resistance value can be set according to requirements.

[0034] See also Figure 2 The rectifier unit 10 includes a rectifier bridge DB1, a fuse F1, a capacitor C1-1, a first input terminal ACN and a second input terminal ACL connected to a power source, and the fuse F1 is connected in series between the first input terminal ACN and the rectifier bridge DB1 to protect the rectifier circuit.

[0035] Furthermore, the filtering unit 20 includes a voltage stabilizing diode RV1 , a capacitor CD1 , a capacitor CD2 , and a resistor R1 connected in parallel.

[0036] In this embodiment, the constant current unit 30 adopts the SM2082G chip, the output current of the chip is set by the adjustment resistor 31 (for example, in the U1 chip, the adjustment resistor 31 is specifically a resistor RS1 and a resistor RS2 connected in parallel), the maximum current of the constant current output terminal OUT can reach 100mA, and the output current does not change with the voltage of the constant current output terminal OUT, and has good constant current performance.

[0037] Since the maximum current of the SM2082G chip is 100 mA, in order to increase the overall current of the constant current unit 30, in this embodiment, a plurality of constant current units 30 are arranged in parallel. In the figure, specifically, five SM2082G chips are connected in parallel.

[0038] See also Figure 3 to Figure 6The present application also provides a direct-down panel light, comprising a back plate 100, a diffuser plate 300, a frame 400, a light-emitting component 200 and the above-mentioned LED driving circuit. Along the thickness direction, the back plate 100 has a first side surface 101 and a second side surface 102 opposite to each other, the first side surface 101 is a light-facing side, and the second side surface 102 is a backlight side. The diffuser plate 300 has a light-transmitting function and is arranged opposite to the back plate 100. The frame 400 is a frame structure formed by connecting a plurality of frame strips (generally 4 strips). The edges of the back plate 100 and the diffuser plate 300 are fixed to the frame 400. The light-emitting component 200 comprises a substrate 220 and LED lamp beads arranged on the substrate 220. The substrate 220 is fixed on the back plate 100 (specifically fixed on the first side surface 101) and is arranged toward the diffuser plate 300.

[0039] See also Figure 5 The substrate 220 is a plurality of parallel strips, the LED lamp beads 231 on the same substrate 220 are arranged along the length direction thereof, and the voltage divider element 240 is arranged between two adjacent LED lamp beads. In addition, considering the problem of uniform light emission, the intervals between two adjacent LED lamp beads 231 in a group are equal.

[0040] In this embodiment, two groups of LED lamp beads are arranged on each substrate 220, and the LED lamp beads of the same group are arranged in series, and the two groups of LED lamp beads are arranged in parallel, respectively, on the left and right sections of the substrate 220. Figure 5 , two groups of LED lamp beads are A and B, each group is provided with 4 LED lamp beads 231, and 4 voltage divider elements 240 are provided between each group. Considering the problem of uniform light emission when the panel light is irradiated, the distance between the last LED lamp bead 231a in group A and the first LED lamp bead 231b in group B is equal to the distance between the two adjacent LED lamp beads in the above group.

[0041] See also Figure 4 The LED lamp beads 231 are distributed in a matrix manner on the inner side of the back plate 100 so that the light source is evenly distributed, and each substrate 220 is connected in parallel through a wire 250 .

[0042] See also Figure 5The back plate 100 is specifically a shell structure, including a bottom wall 110 and a side wall 120. The bottom wall 110 is arched to facilitate the installation and fixing of the light bar 210. The back plate 100 can be formed by stamping a metal plate. The frame strip 410 has a first mounting surface 411 and a second mounting surface 412, and the first mounting surface 411 is higher than the second mounting surface 412. The edge of the back plate 100 overlaps the higher first mounting surface 411, and the diffuser plate 300 overlaps the lower second mounting surface 412. The edge area of ​​the side wall 120 is partially concave to press against the edge of the diffuser plate 300, and the diffuser plate 300 is clamped and fixed with the second mounting surface 412 to prevent the edge area of ​​the diffuser plate 300 from bending, thereby preventing the central area of ​​the back plate 100 from collapsing downward.

[0043] The LED lamp bead 231 is covered with a lens 232 , and the emitted light passes through the lens 232 and the diffusion plate 300 in sequence. After the light is diffused, the numerous LED point light sources form a uniform surface light source.

[0044] The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification. When the technical features in different embodiments are embodied in the same figure, it can be regarded that the figure also discloses the combination examples of the various embodiments involved.

[0045] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application.

Claims

1. LED driving circuit, used to provide direct current to LED lamp beads, including a rectifier unit, a filter unit and a constant current unit, characterized in that: The LED lamp bead is connected in series between the filter unit and the constant current unit. The constant current unit is used to output a stable current to the LED lamp bead, and has a constant current output end, a current regulating end and a grounding end. The constant current output end is connected in series with the LED lamp bead, and the current regulating end is grounded through an adjusting resistor. The LED driving circuit also includes a voltage divider element connected in series with the LED lamp bead.

2. The LED driving circuit according to claim 1, characterized in that: The voltage dividing element is a resistor.

3. The LED driving circuit according to claim 1, characterized in that: The filtering unit includes a voltage stabilizing diode RV1, a capacitor CD1, a capacitor CD2 and a resistor R1 connected in parallel.

4. The LED driving circuit according to claim 1, characterized in that: The constant current units are multiple and arranged in parallel.

5. Direct-down panel light, characterized in that: It includes a back plate, a diffusion plate, a frame, a light-emitting component and the LED driving circuit as described in any one of claims 1 to 4, wherein the back plate is arranged opposite to the diffusion plate, the frame is a frame structure formed by connecting a plurality of frame strips, the edges of the back plate and the diffusion plate are fixed to the frame, the light-emitting component includes a substrate and LED lamp beads arranged on the substrate, the substrate is fixed on the back plate and arranged toward the diffusion plate.

6. The direct-down panel light according to claim 5, characterized in that: The substrate is a plurality of parallel arranged substrates, the LED lamp beads on the same substrate are arranged along the length direction thereof, and the voltage dividing element is arranged between two adjacent LED lamp beads.

7. The direct-down panel light according to claim 5, characterized in that: Two groups of LED lamp beads are arranged on each substrate. The LED lamp beads in the same group are arranged in series, and the two groups of LED lamp beads are arranged in parallel, respectively, on the left and right sections of the substrate.

8. The direct-down panel light according to claim 5, characterized in that: The LED lamp bead is covered with a lens.

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