Low-voltage light-emitting diode (LED) lamp strip capable of changing light

Abstract

The utility model discloses a light-variable low-voltage LED lamp strip which comprises a circuit board, the circuit board comprises a circuit layer and an upper insulating layer covering the front face of the circuit layer, a plurality of light-emitting modules are arranged on the circuit board, and each light-emitting module is formed by reversely connecting the positive electrode and the negative electrode of a first LED lamp bead and the positive electrode and the negative electrode of a second LED lamp bead which are different in color temperature. The first LED lamp bead and the second LED lamp bead are high-voltage LED lamp beads which are matched with a driving power supply after being connected with resistors in series, the circuit layer comprises a first circuit, a second circuit and a third circuit, the light-emitting modules are connected between the first circuit and the second circuit in parallel, one resistor is arranged every a plurality of light-emitting modules, and the third circuit is connected between the first circuit and the second circuit. And one end of the resistor is connected to the second circuit, and the other end of the resistor is connected to the third circuit. The utility model has the advantages of less resistor consumption, simple circuit, small circuit board width dimension, short minimum shearing unit, easy accurate matching of the shearing length with the actual requirement, and the like.

Description

Technical Field

[0001] This utility model relates to an LED lighting fixture, specifically disclosing a variable light low-voltage LED light strip. Background Technology

[0002] refer to Figure 1 The existing low-voltage variable-brightness LED light strip includes multiple parallel-connected light-emitting modules D. Each light-emitting module D includes a pure white light unit D1 composed of multiple pure white LEDs and resistors connected in series, and a warm white light unit D2 composed of multiple warm white LEDs and resistors connected in series. The positive terminals of the pure white light unit D1 and the warm white light unit D2 are connected to the positive circuit V+, and their negative terminals are connected to two negative circuits V- respectively. An external controller controls the brightness ratio of the two light-emitting units D1 / D2 in the light-emitting module D through the two negative circuits, enabling the LED light strip to achieve a color temperature change from pure white to warm white light. When using the LED light strip, it needs to be cut to the actual length. To avoid damaging the circuit structure of the light-emitting modules, one light-emitting module D should be used as the smallest cutting unit. Low-voltage LED light strips typically have an input voltage of 12V or 24V, while ordinary LED beads operate at 3V. The light-emitting units D1 / D2 in the light-emitting module D require multiple LED beads connected in series, and each light-emitting unit D1 / D2 needs a series resistor to suppress voltage surges. This results in the light-emitting module D occupying a large space along the length of the circuit board, leading to a longer minimum cutting unit length for the LED light strip, making it difficult to accurately match the actual usage dimensions. Furthermore, because it requires five circuits to be arranged along the width of the circuit board, the circuitry is complex, resulting in a larger circuit board width. Utility Model Content

[0003] Therefore, it is necessary to provide a variable light low-voltage LED light strip with a short minimum cutting unit, simple circuit, and small circuit board width to address the problems of existing technology.

[0004] To address the problems of existing technologies, this utility model discloses a variable light low-voltage LED light strip, comprising a circuit board, a circuit layer, and an upper insulating layer covering the front of the circuit layer. Multiple light-emitting modules are arranged on the circuit board. Each light-emitting module consists of a first LED bead and a second LED bead with different color temperatures connected in reverse polarity. The first and second LED beads are high-voltage LED beads matched to a driving power supply after being connected in series with a resistor. The circuit layer includes a first circuit, a second circuit, and a third circuit. The light-emitting modules are connected in parallel between the first and second circuits. A resistor is provided every few light-emitting modules, with one end of the resistor connected to the second circuit and the other end connected to the third circuit.

[0005] The beneficial effects of this utility model are as follows: Because this utility model uses high-voltage LED beads, the light-emitting module contains only two LED beads with different color temperatures. The length of the light-emitting module is relatively short. Furthermore, because the two LED beads in the light-emitting module are connected with reversed positive and negative terminals, the light-emitting module and the resistor are connected in a series-parallel hybrid connection. Multiple light-emitting modules share multiple resistors, eliminating the need to configure a resistor for each light-emitting module. This results in fewer resistors, lower power consumption, simpler circuitry, fewer control lines, smaller circuit board width, shorter minimum cutting unit, and easier to accurately match the cutting length to actual needs. Even if a very short section of the light-emitting module without resistors is cut in the middle, it can still be used after being connected to other light-emitting modules that contain resistors.

[0006] This utility model can be further improved as follows: the driving voltage of the LED light strip is 12V, 24V, or 36V, and the working voltage of the LED beads is 9V, 18V, or 33V respectively. In the second circuit, a break is provided at intervals between several light-emitting modules. On the upper insulating layer, a wiring pad exposing the first and second circuits is provided at each interval between light-emitting modules. A resistor is provided next to each light-emitting module at both ends of the light strip, and a resistor is provided every two light-emitting modules in the middle of the light strip. A middle insulating layer can also be provided between the circuit layer and the middle insulating layer, and a first auxiliary circuit and a second auxiliary circuit, respectively electrically connected to the first and second circuits, are provided between the middle insulating layer and the circuit layer. Attached Figure Description

[0007] Figure 1 This is a circuit schematic diagram of existing technology.

[0008] Figure 2 This is a front structural view of the LED light strip of this utility model.

[0009] Figure 3 This is a circuit structure diagram of the circuit board of this utility model.

[0010] Figure 4 This is the circuit schematic diagram of this utility model.

[0011] Figure 5 This is a schematic diagram of the control principle of this utility model. Detailed Implementation

[0012] To further understand the features, technical means, and specific objectives and functions achieved by this utility model, the following detailed description of this utility model is provided in conjunction with the accompanying drawings and specific embodiments.

[0013] refer to Figure 2 A variable light low-voltage LED light strip includes a circuit board 1 and a first LED bead 21, a second LED bead 22, and a resistor 3 with different color temperatures soldered onto the circuit board 1.

[0014] refer to Figure 3 The circuit board 1 includes a circuit layer, a lower insulating layer disposed on the back of the circuit layer, and an upper insulating layer 10 on the front of the circuit board. A first circuit 11, a second circuit 12, and a third circuit 13 extending along the length of the circuit board are disposed on the circuit layer. The first circuit 11 and the third circuit 13 are located on opposite sides of the circuit board, and the second circuit 12 is located between the first circuit 11 and the third circuit 13. A wiring pad 101 is provided on the upper insulating layer 10 above the first circuit 11 and the third circuit 13, an LED bead pad 102 is provided above the first circuit 11 and the second circuit 12, and a resistor pad 103 is provided above the second circuit 12 and the third circuit 13. The wiring pad 101 is used to solder leads to connect to an external controller and a drive power supply. The first LED bead 21 and the second LED bead 22 are soldered into the LED bead pad 102, and the resistor 3 is soldered into the resistor pad 103. An intermediate insulating layer may be provided between the circuit layer and the intermediate insulating layer, and a first auxiliary circuit and a second auxiliary circuit may be provided between the intermediate insulating layer and the circuit layer. A conductor penetrating the intermediate insulating layer may be provided in the area of ​​the wiring pad, so that the first auxiliary circuit and the second auxiliary circuit are electrically connected to the first circuit 11 and the second circuit 12, respectively. This can increase the conductive cross-sectional area of ​​the first circuit 11 and the second circuit 12, reduce resistance, and reduce circuit voltage drop.

[0015] refer to Figure 3 and Figure 4 The first LED bead 21 and the second LED bead 22 are high-voltage LED beads. That is, each LED bead contains multiple LED chips connected in series, each with a single operating voltage of 3V. Depending on the number of LED chips connected in series, the operating voltage of the LED bead can range from 9V to 33V. When powered by a 12V external power supply, the LED bead contains three LED chips, and the operating voltage is 9V; when powered by a 24V external power supply, the LED bead contains six LED chips, and the operating voltage is 18V; when powered by a 36V external power supply, the LED bead can contain nine to eleven LED chips, and the operating voltage is 27V to 33V. These high-voltage LED beads can be adapted to the voltage of the external power supply by connecting a resistor of appropriate value in series (see reference). Figure 4A first LED bead 21 and a second LED bead 22 are connected with their positive and negative terminals reversed to form a light-emitting module 2. One end of the light-emitting module 2 is connected to the first circuit 11, and the other end is connected to the second circuit 12. One end of the resistor 3 is connected to the second circuit 12, and the other end is connected to the third circuit 13. That is, all light-emitting modules 2 are first connected in parallel between the first circuit 11 and the second circuit 12, and all resistors 3 are connected in parallel between the second circuit 12 and the third circuit, and then the light-emitting modules 2 and resistors 3 are connected in series. As a further improvement of this utility model, two resistors 3 are placed next to the light-emitting modules 2 at both ends of the LED strip, and one resistor 3 is placed every two or more light-emitting modules 2 in the middle of the LED strip. In this way, no matter which end of the strip is cut, and no matter the length of the cut, at least one resistor 3 will be included, making cutting more convenient. Each light-emitting module 2 is provided with a pair of wiring pads 101 at intervals. Thus, this invention can be used by cutting from any pair of wiring pads 101 and soldering leads onto the wiring pads 101 to connect to an external driving power supply, achieving what is known in the industry as arbitrary cutting of light-emitting modules 2. To avoid the entire light strip failing to light up due to a short circuit of a single LED, which would be inconvenient for use and troubleshooting, a break 121 is provided on the second circuit 12 every six to eighteen light-emitting film groups 2. This way, even if an LED short-circuits, only that part of the light-emitting module 2 will not light up, allowing for quick troubleshooting and repair.

[0016] refer to Figure 5 The external controller of this invention can employ a MOSFET H-bridge circuit or a dedicated IC to control the voltage polarity across the light-emitting module 2 at a high frequency, thereby achieving the effect of simultaneous illumination of the two reverse-connected LED beads in the light-emitting module 2. Taking the MOSFET H-bridge circuit as an example: when PWM1 and PWM4 are at high potentials and PWM2 and PWM3 are at low potentials, the first MOSFET Q1 and the fourth MOSFET Q4 are turned on, and the first LED bead 21 is lit; conversely, when PWM1 and PWM4 are at low potentials and PWM2 and PWM3 are at high potentials, the second MOSFET Q2 and the third MOSFET Q3 are turned on, and the second LED bead 22 is lit. The voltage polarity switching frequency across the light-emitting module 2 is above the hundreds of kilohertz level, and the switching traces cannot be detected by the naked eye. Thus, visually, both the first LED bead 21 and the second LED bead 22 in the light-emitting module 2 appear to be constantly lit.

[0017] This invention uses high-voltage LED beads, and the light-emitting module contains only two LED beads of different color temperatures, resulting in a shorter module length. Furthermore, because the two LED beads within the light-emitting module are connected with reversed polarity, the control circuitry on the circuit board is reduced. Additionally, because the light-emitting module and resistors are connected in a mixed series-parallel configuration, multiple light-emitting modules share multiple resistors, eliminating the need for a separate resistor for each module. This reduces resistor usage, power consumption, and simplifies the circuitry, reducing control lines and the circuit board width. The minimum cutting unit is short, making it easier to precisely match the cutting length to actual needs. Even if a very short section of the light-emitting module without resistors is cut, it can still be used after being connected to other light-emitting modules containing resistors.

[0018] The above-described embodiments are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A variable-light low-voltage LED light strip, comprising a circuit board, the circuit board including a circuit layer and an upper insulating layer covering the front side of the circuit layer, wherein multiple light-emitting modules are disposed on the circuit board, characterized in that: The light-emitting module consists of two LED beads with different color temperatures, a first LED bead and a second LED bead, with their positive and negative terminals reversed. The first LED bead and the second LED bead are high-voltage LED beads matched with the driving power supply after being connected in series with a resistor. The circuit layer includes a first circuit, a second circuit and a third circuit. The light-emitting module is connected in parallel between the first circuit and the second circuit. A resistor is set every few light-emitting modules. One end of the resistor is connected to the second circuit and the other end is connected to the third circuit.

2. The variable light low-voltage LED light strip according to claim 1, characterized in that: The LED light strip is driven by 12V, 24V, or 36V, and the LED beads are operated by 9V, 18V, or 33V respectively.

3. The variable light low-voltage LED light strip according to claim 1, characterized in that: The second circuit has breaks at intervals of several light-emitting modules.

4. The variable light low-voltage LED light strip according to claim 1, characterized in that: On the upper insulating layer, there are bonding pads that expose the first circuit and the second circuit in each light-emitting module spacing.

5. A variable light low-voltage LED light strip according to claim 1, characterized in that: A resistor is installed next to each of the light-emitting modules at both ends of the light strip, and a resistor is installed every two light-emitting modules in the middle of the light strip.

6. A variable light low-voltage LED light strip according to claim 1, characterized in that: A middle insulating layer may also be provided between the circuit layer and the middle insulating layer, and a first auxiliary circuit and a second auxiliary circuit, which are electrically connected to the first circuit and the second circuit respectively, may be provided between the middle insulating layer and the circuit layer.

Images