Alternating current direct drive light source

Abstract

This utility model discloses an AC direct-drive light source, including a lamp body, a driver, and an AC power supply circuit. The lamp body is composed of LED series modules, the driver consists of a driver chip and its peripheral circuits, and the AC power supply circuit consists of a rectifier bridge, a filter capacitor, and a discharge resistor. The driver uses AC mains voltage for direct drive, and the AC power supply circuit provides power to the entire solution. The AC direct-drive solution can output a higher drive voltage, resulting in significantly lower current when transmitting the same power compared to traditional low-voltage drive solutions. This leads to less line loss and reduced heat generation in the drive circuit. Integrating the lamp body, driver, and AC power supply circuit onto the same metal substrate not only meets the power requirements of the UV lamp but also saves PCB size. Furthermore, the metal substrate allows for better heat conduction to an external heat sink, effectively meeting the stringent requirements of high-power UV lamps in terms of power consumption, size, and reliability.

Description

Technical Field

[0001] This utility model relates to the field of LED driving and packaging technology, and in particular to an AC direct-drive light source. Background Technology

[0002] Due to their unique applications in curing, sterilization, and medical fields, ultraviolet (UV) lamps are developing towards higher power and higher luminous intensity. Traditional UV LED light sources typically employ a modular design, where an independent AC / DC switching power supply and LEDCOB (Chip on Board) light source are connected separately via cables. This traditional architecture has the following inherent drawbacks: 1. Large equipment size and low integration: High-power switching power supplies are inherently bulky and difficult to integrate compactly with the light source, which limits the miniaturization and lightweight design of terminal products.

[0003] 2. Low heat dissipation efficiency: The driver power supply and LEDCOB are two independent heat sources, usually installed in different locations or on heat sinks, which increases the thermal management burden of the overall system. This separate and non-coplanar heat dissipation method is inefficient and restricts the further improvement of the power density of the equipment. Utility Model Content

[0004] To overcome the shortcomings of the aforementioned background technology, this utility model provides an AC direct-drive light source. By integrating the lamp body and the driver on the same metal substrate, it not only meets the power requirements of the ultraviolet lamp, but also saves the size of the PCB, making it easier to design a better heat dissipation method, and strongly promotes the development of equipment towards miniaturization and high power density.

[0005] An AC direct-drive light source, characterized in that it comprises: The lamp body is a light-emitting module composed of several LED beads connected in series; The driver is a constant current driving circuit composed of several LED driver chips; The AC power supply circuit accepts direct AC mains power input, which, after rectification and filtering, powers the lamp body together with the driver section.

[0006] To further explain, several of the aforementioned LED beads are connected in series to form an LED series module, and the LED beads are light-emitting diodes.

[0007] To further explain, the LED series module integrates multiple LED beads in series on a metal substrate using a COB method. One end of the LED series module is connected to the AC power supply circuit, and the other end is connected to the LED driver chip.

[0008] To further explain, in the LED series module, the anode of the first LED D1 is connected to the positive terminal of the constant current driving circuit, its cathode is connected to the anode of the second LED D2, the cathode of the second LED D2 is connected to the anode of the third LED D3, adjacent LEDs are connected to each other, until the cathode of the last LED is connected to the negative terminal of the constant current driving circuit.

[0009] To further clarify, the light-emitting diode is an ultraviolet light-emitting diode.

[0010] To further explain, there are multiple LED driver chips, and the outputs of the multiple LED driver chips are connected in parallel to jointly drive the light-emitting module.

[0011] To further explain, the AC power supply circuit includes a rectifier bridge, a capacitor filter circuit, and a resistor discharge circuit. The rectifier bridge converts AC power into DC power; the capacitor filter circuit filters out instantaneous interference from the AC power supply; and the resistor discharge circuit discharges the circuit after the light-emitting module is turned off to improve circuit safety.

[0012] To further clarify, the withstand voltage of the LED driver chip exceeds 400V.

[0013] To further clarify, the rectifier bridge is model ABS210.

[0014] To further clarify, the capacitors used in the capacitor filter circuit have a voltage rating exceeding 400V.

[0015] The beneficial effects of this utility model are as follows: The LED series module uses a COB (Chip-on-Board) method to integrate multiple LED chips in series on a metal substrate. This allows the LED series module to operate at higher voltages (such as tens to hundreds of volts) and lower currents. The driver uses a direct AC voltage drive method. The AC direct drive solution can output a higher drive voltage, resulting in a significantly lower current when transmitting the same power compared to traditional low-voltage drive solutions. This reduces line losses and heat generation in the drive circuit. Integrating the lamp body and driver on the same metal substrate not only meets the power requirements of the UV lamp but also saves PCB size. Furthermore, the metal substrate allows for better heat conduction to the external heat sink, effectively meeting the stringent requirements of high-power UV lamps for power consumption, size, and reliability. Attached Figure Description

[0016] Figure 1 This is the circuit schematic diagram of the LED driver chip of this utility model.

[0017] Figure 2 This is a circuit diagram of the AC power supply circuit of this utility model.

[0018] Figure 3 This is the circuit diagram of the LED series module of this utility model. Detailed Implementation

[0019] The present invention will be further described below with reference to specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0020] like Figures 1 to 3 The present invention discloses an AC direct-drive light source, comprising a lamp body, a driver, and an AC power supply circuit. The lamp body is composed of an LED series module (light-emitting module), which consists of several LED beads connected in series. The LED beads are light-emitting diodes. The LED series module integrates multiple LED beads in series on a metal substrate using a COB method. One end of the LED series module is connected to the AC power supply circuit, and the other end is connected to the LED driver chip. The LED driver module includes eight parallel LED driver chips, model MT7606B. The drive control terminal of the LED driver chip is connected to the negative terminal of the LED series module to control the brightness of the LED lamp. The present invention also includes an AC power supply circuit connected to the LED series module. The positive output terminal of the AC power supply circuit is connected to the positive terminal of the LED series module. This direct-drive method can output a higher drive voltage, resulting in a significantly lower current than traditional low-voltage drive schemes when transmitting the same power, less line loss, and less heat generated in the drive circuit.

[0021] In the LED series module, the anode of the first LED D1 is connected to the positive terminal of the constant current drive circuit, and its cathode is connected to the anode of the second LED D2. The cathode of the second LED D2 is connected to the anode of the third LED D3. Adjacent LEDs are connected to each other until the cathode of the last LED is connected to the negative terminal of the constant current drive circuit.

[0022] The number of LED driver chips can be multiple, specifically eight, ten, twelve, etc. It should be noted that these numbers are only preferred options and not restrictive regulations. The outputs of multiple LED driver chips are connected in parallel to drive the light-emitting module (lamp body) to work. The withstand voltage of the LED driver chips exceeds 400V, and the AC power can be directly supplied to the LED driver chips after rectification.

[0023] The AC power supply circuit includes a rectifier bridge, a capacitor filter circuit, and a resistor discharge circuit. The rectifier bridge converts AC power into DC power, and its model is related to the operating voltage and current of the LED module. The capacitor filter circuit filters out instantaneous interference from the AC power supply. The capacitors used in the capacitor filter circuit need to have a withstand voltage of over 400V, and the number and capacitance of the capacitors need to be changed according to the design requirements. The resistor discharge circuit discharges the circuit after the LED module is turned off, improving circuit safety. The resistance value of the resistor discharge circuit is related to the required discharge time.

[0024] In one preferred embodiment, the number of light-emitting diodes is about 35, which corresponds to an AC voltage of 110V.

[0025] In one preferred embodiment, the number of light-emitting diodes is about 70, which corresponds to a 220V AC voltage.

[0026] In this embodiment, as Figure 3 As shown, the LED series module includes seventy LEDs connected in series. The LEDs are ultraviolet LEDs. The anode of the first LED D1 is connected to the AC power supply circuit, and its cathode is connected to the anode of the second LED D2. The cathode of the second LED D2 is connected to the anode of the third LED D3. The cathodes and anodes of adjacent LEDs are connected to each other, up to the seventieth LED D70. The cathode of the seventieth LED D70 is connected to the LED driver chip, so that the current output from the AC power supply circuit flows sequentially through D1, D2, D3...D69, D70, forming a continuous series path, and finally flows into the LED driver chip, forming a complete circuit. Of course, in other embodiments, the LED series module can use any number of LEDs, and the LEDs can be visible light LEDs or invisible light LEDs. It should be noted that the use of ultraviolet LEDs is only a preferred option and is not a limiting factor.

[0027] The cathode of the seventieth LED D70 is connected to the fifth, sixth, seventh, and eighth pins of the LED driver chip, respectively.

[0028] like Figure 1The first pin of the LED driver chip shown is grounded. Its second, third, and fourth pins are connected to one end of a resistor, and the other end of the resistor is grounded. There are eight LED driver chips and eight resistors. Each resistor is connected to the second, third, and fourth pins of its corresponding LED driver chip. The specific connection relationships are as follows: the first LED driver chip U1 is connected to the second resistor R2; the second LED driver chip U2 is connected to the third resistor R3; the third LED driver chip U3 is connected to the fourth resistor R4; the fourth LED driver chip U4 is connected to the fifth resistor R5; the fifth LED driver chip U5 is connected to the sixth resistor R6; the sixth LED driver chip U6 is connected to the seventh resistor R7; the seventh LED driver chip U7 is connected to the eighth resistor R8; and the eighth LED driver chip U8 is connected to the ninth resistor R9. R2-R9 are all grounded.

[0029] like Figure 2 The AC power supply circuit shown includes a rectifier bridge. This circuit provides DC power after power factor correction (PFC) and rectification, or a drive signal of a specific frequency, to provide the initial operating voltage and current for the LED series module. The rectifier bridge is an ABS210. The first pin of the rectifier bridge is connected to the neutral wire N1, the second pin is connected to the live wire L1, and the third pin is connected to the anode of the first light-emitting diode D1. The third pin also connects to a first resistor R1 and nine capacitors: C1, C2, C3, C4, C5, C6, C7, C8, and C9. The other ends of the first resistor R1 and the nine capacitors (C1-C9) are all grounded. The fourth pin of the rectifier bridge is also grounded. The rectifier bridge converts AC mains power into DC power.

[0030] Working principle: When the LED series module needs to be lit, the 220V AC power is converted into DC power by the AC power supply circuit (AC direct drive module). The DC power then flows to the LED series module, and the light-emitting diodes light up after being powered on. The LED driver chip is responsible for receiving the current signal at the end of the series circuit and performing precise constant current control and overcurrent protection. Through internal or external feedback mechanisms, it dynamically adjusts the output to ensure that the current flowing through all 70 LEDs is stable and consistent, avoiding damage to the light-emitting diodes or uneven brightness due to current fluctuations.

[0031] This achieves the following effect: the LED series module uses the COB method to integrate multiple LED beads in series on a metal substrate (such as aluminum or copper), so that the LED series module can operate at higher voltages (such as tens to hundreds of volts) and lower currents. The driver adopts a direct AC voltage drive method. The AC direct drive solution can output a higher drive voltage, which results in a significantly lower current when transmitting the same power compared to traditional low-voltage drive solutions. This reduces line loss and heat generation in the drive circuit. By integrating the lamp body and driver onto the same metal substrate, the power requirements of the UV lamp can be met while saving PCB size. Furthermore, the metal substrate can better conduct heat to the external heat sink, effectively meeting the stringent requirements of high-power UV lamps for power consumption, size, and reliability.

[0032] In a preferred embodiment, this driver power supply can also be used with other types of LED series modules. Even LED series modules with a large number of LED beads can effectively meet the requirements of power consumption, size and reliability.

[0033] The present application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present application. Therefore, the content of this specification should not be construed as a limitation of the present application.

Claims

1. An AC direct-drive light source, characterized in that, include: The lamp body is a light-emitting module composed of several LED beads connected in series; The driver is a constant current driving circuit composed of several LED driver chips; The AC power supply circuit accepts direct AC mains power input, which, after rectification and filtering, powers the lamp body together with the driver section.

2. The AC direct-drive light source according to claim 1, characterized in that, A number of LED beads are connected in series to form an LED series module, wherein the LED beads are light-emitting diodes.

3. The AC direct-drive light source according to claim 2, characterized in that, The LED series module integrates multiple LED beads in series on a metal substrate using the COB method. One end of the LED series module is connected to the AC power supply circuit, and the other end is connected to the LED driver chip.

4. The AC direct-drive light source according to claim 2, characterized in that, In the LED series module, the anode of the first LED D1 is connected to the positive terminal of the constant current driving circuit, and its cathode is connected to the anode of the second LED D2. The cathode of the second LED D2 is connected to the anode of the third LED D3. Adjacent LEDs are connected to each other until the cathode of the last LED is connected to the negative terminal of the constant current driving circuit.

5. An AC direct-drive light source according to claim 2, characterized in that, The light-emitting diode is an ultraviolet light-emitting diode.

6. The AC direct-drive light source according to claim 1, characterized in that, The LED driver chip is a plurality of chips, and the outputs of the plurality of LED driver chips are connected in parallel to drive the light-emitting module to work.

7. An AC direct-drive light source according to claim 1, characterized in that, The AC power supply circuit includes a rectifier bridge, a capacitor filter circuit, and a resistor discharge circuit. The rectifier bridge converts AC power into DC power. The capacitor filter circuit filters out instantaneous interference from the AC power supply. The resistor discharge circuit discharges the circuit after the light-emitting module is turned off to improve circuit safety.

8. An AC direct-drive light source according to claim 6, characterized in that, The LED driver chip has a withstand voltage of over 400V.

9. An AC direct-drive light source according to claim 7, characterized in that, The rectifier bridge is model ABS210.

10. An AC direct-drive light source according to claim 7, characterized in that, The capacitors used in the capacitor filter circuit have a voltage rating exceeding 400V.

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