Manufacturing method of LED lighting module and LED lighting module

Abstract

The invention discloses a method for manufacturing an LED lighting module and the LED lighting module, wherein the method for manufacturing the LED lighting module firstly adopts a pressed substrate to make an insulating through hole, which has universality and does not require pressing specially designed through holes for different products. The manufacturing method is simple, the yield rate is high, and the cost is low. At the same time, the LED lighting module adopts an LED constant current driving circuit with a filter module, a rectifier bridge, a primary clamping protection module, a current output module, a primary feedback control module, a delay module, a current sampling module and a buffer module to drive the LED, the circuit structure is simple, the LED element is effectively protected, and the service life of the LED element is extended.

Description

[0001] The present invention is a divisional application of the application with application date of 2018.08.20, application number of 2018109498877, and invention name of “Substrate with insulating through hole, manufacturing method and LED lighting module”. Technical Field

[0002] The present invention relates to the technical field of PCB board heat dissipation, and in particular to a manufacturing method of an LED lighting module and the LED lighting module. Background Art

[0003] As electronic and industrial products develop towards miniaturization and centralization, high-power miniaturization of LED substrates is becoming more and more popular. Miniaturization requires higher precision for the thermal conductivity and heat dissipation of the substrate, as well as the circuits and pads on the substrate. In order to solve the problems of thermal conductivity and heat dissipation, substrate materials with good thermal conductivity and heat dissipation are usually selected to replace glass fiber board substrates, which increases the material cost. On the other hand, drilling holes for heat dissipation is also a common solution. Traditional glass fiber boards can be directly drilled due to their own insulation properties, but since metal plates are good conductors of electricity, the substrate through holes need to be insulated when making insulating through holes. At present, the drilling of the substrate is to first drill holes in the metal plate, then fill the holes with insulating materials, then laminate the metal plate with other plates, and then drill holes on the laminated substrate. In this way, after filling the holes with insulating materials, the lamination requires scraping glue, baking glue, and drawing, and the lamination is prone to cause pores, blistering, and other problems, making the product unqualified.

[0004] The LED on the substrate serves as the light source of the lighting appliance and requires a constant current when working, so a special driving circuit is needed. At present, LED driving circuits all adopt a constant current driving mode to avoid the situation where the current flowing through the LED changes when the voltage and temperature change, causing damage to the LED. However, most of the existing LED constant current driving circuits have complex structures and lack overvoltage protection circuits. If the output voltage exceeds the required specifications, the LED is easily damaged, affecting the use effect and service life of the LED display panel. Summary of the invention

[0005] Based on the above problems, the present invention provides a substrate with insulating through holes, a manufacturing method and an LED lighting module to solve the problems of the existing through hole substrate structure, complex manufacturing process, low yield rate and complex LED driving circuit thereon.

[0006] In the first aspect, the present invention discloses a substrate with an insulating through hole, comprising: a metal plate, an insulating plate, a copper foil circuit, a through hole, and an insulating member; the insulating plate is provided with a first contact surface and a second contact surface, the first contact surface is arranged opposite to the second contact surface, the metal plate abuts against the first contact surface, the copper foil circuit abuts against the second contact surface, the hole wall of the through hole is composed of the insulating plate, the copper foil circuit and the insulating member, and the insulating member is detachably connected to the metal plate.

[0007] In a second aspect, the present invention further discloses a method for manufacturing a substrate having an insulating through hole, comprising the following steps:

[0008] S1. Provide a pre-treated metal plate, an insulating plate and a copper foil circuit, and laminate the metal plate, the insulating plate and the copper foil circuit to produce a metal substrate;

[0009] S2, providing a protective film on the metal plate, and forming a blind hole on the metal plate by drilling, wherein the distance between the bottom of the blind hole and the insulating plate is 0 mm to 0.1 mm;

[0010] S3, removing part of the metal plate residue between the bottom of the blind hole and the insulating plate by a mechanical processing method to expose the insulating plate;

[0011] S4, removing the protective film on the metal plate surface, filling the blind hole with liquid insulating resin, and waiting for a certain period of time for the liquid insulating resin to solidify;

[0012] S5. A through hole is formed on the cured insulating resin by a drilling process to obtain the substrate with an insulating through hole as described in the first aspect, wherein the geometric center of the cross section of the through hole is the same as that of the cross section of the blind hole, and the through hole is located inside the blind hole.

[0013] Preferably, the mechanical processing method includes: laser ablation processing and etching processing.

[0014] In a third aspect, the present invention further discloses an LED lighting module, comprising: a substrate and an LED constant current drive circuit arranged on the substrate, wherein the substrate is the substrate with insulating through holes described in the first aspect.

[0015] Preferably, the LED constant current drive circuit comprises: a filter module, a rectifier bridge, a primary clamp protection module, a current output module, a primary feedback control module, a delay module, a current sampling module and a buffer module; the filter module filters the current input by the rectifier bridge and inputs the current into the primary clamp protection module; the primary clamp protection module outputs a constant current signal to the current output module according to the signal received from the primary feedback control module; the primary feedback control module compares the current feedback from the current output module with the current collected by the current sampling module and outputs a current signal to the primary clamp protection module; the current sampling module inputs the collected current of the buffer module into the primary clamp protection module via the delay module.

[0016] Preferably, the filtering module includes: a first inductor, a first resistor, a first capacitor and a second capacitor; the first end of the first resistor is connected to the input end of the rectifier bridge, and the second end of the first resistor is connected to the primary clamping protection circuit; the first resistor is connected in parallel with the first inductor; the first end of the first capacitor is electrically connected to the first end of the first resistor, and the second end of the first capacitor is grounded; the first end of the second capacitor is electrically connected to the second end of the first resistor, and the second end of the second capacitor is grounded.

[0017] Preferably, the primary clamping protection module includes a second resistor, a third resistor, a third capacitor, a fourth resistor, a fifth resistor and a first diode; the first end of the second resistor is electrically connected to the second end of the first resistor, the second end of the second resistor is connected to the first end of the third resistor, and the second end of the third resistor is connected to the primary feedback control module; the first end of the third capacitor is connected to the first end of the second resistor, the second end of the third capacitor is connected to the first end of the fifth resistor, the fourth resistor is connected to the third capacitor in parallel, the first end of the fourth resistor is connected to the current output module, and the second end of the fourth capacitor is connected to the first end of the fifth resistor; the second end of the fifth resistor is electrically connected to the negative electrode of the first diode, and the positive electrode of the first diode is connected to the buffer module and the current output module.

[0018] Preferably, the buffer module includes: a first switch tube, a sixth resistor, a seventh resistor and a ninth capacitor; the first end of the first switch tube is electrically connected to the positive electrode of the first diode, the second end of the first switch tube is connected to the current sampling module, and the third end of the first switch tube is connected to the first end of the sixth resistor and the first end of the seventh resistor; the second end of the sixth resistor is connected to the primary feedback control module, and the second end of the seventh resistor is connected to the current sampling module and the delay module; the ninth capacitor is connected in parallel with the first switch tube.

[0019] Preferably, the delay module includes: an eighth resistor and a fourth capacitor; the first end of the eighth resistor is connected to the second end of the seventh resistor and the current sampling module, and the second end of the eighth resistor is connected to the first end of the fourth capacitor and the primary feedback control module; the first end of the fourth capacitor is connected to the primary feedback control module, and the second end of the fourth capacitor is grounded.

[0020] Preferably, the current sampling module includes a ninth resistor and a tenth resistor; the first end of the ninth resistor is connected to the second end of the first switch tube and the first end of the eighth resistor, and the second end of the ninth resistor is grounded; the tenth resistor is connected in parallel with the ninth resistor, the first end of the tenth resistor is electrically connected to the first end of the eighth resistor, and the second end of the tenth resistor is grounded.

[0021] In summary, the present invention provides a substrate with insulating through holes, a manufacturing method and an LED lighting module, wherein the substrate with insulating through holes comprises: a metal plate, an insulating plate, a copper foil circuit, a through hole, and an insulating member. The substrate has a simple structure and the metal plate has a low cost. The manufacturing method of the substrate with insulating through holes first uses a laminated substrate to make insulating through holes, which is universal and does not require laminating of specially designed through holes for different products. At the same time, it also avoids the scraping, baking and wire drawing steps required for laminating after filling with insulating material. The manufacturing method is simple, the yield is high and the cost is low. At the same time, the LED lighting module uses an LED constant current drive circuit with a filter module, a rectifier bridge, a primary clamping protection module, a current output module, a primary feedback control module, a delay module, a current sampling module and a buffer module to drive the LED. The circuit structure is simple, the LED components are effectively protected, and the service life of the LED components is extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of a substrate with insulating through holes according to the present invention.

[0023] Figure 2 The present invention is a flow chart of a method for manufacturing a substrate with insulating through holes.

[0024] Figure 3 Schematic diagram of the LED constant current driving circuit of the present invention. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0026] See also Figure 1The present invention discloses a substrate with an insulating through hole, comprising: a metal plate 11, an insulating plate 12, a copper foil circuit 13, a through hole 14, and an insulating member 15; the insulating plate 12 is provided with a first contact surface 121 and a second contact surface 122, the first contact surface 121 and the second contact surface 122 are arranged opposite to each other, the metal plate 11 abuts against the first contact surface 121, the copper foil circuit 13 abuts against the second contact surface 122, the hole wall of the through hole 14 is composed of the insulating plate 12, the copper foil circuit 13 and the insulating member 15, and the insulating member 15 is detachably connected to the metal plate 11. The metal plate 11 can be an aluminum plate, a copper plate or a metal alloy plate, and the specific material of the metal plate 11 is not limited here.

[0027] See also Figure 2 The present invention also discloses a method for manufacturing a substrate having an insulating through hole, comprising the following steps:

[0028] S1. Provide a pre-treated metal plate, an insulating plate and a copper foil circuit, and laminate the metal plate, the insulating plate and the copper foil circuit to produce a metal substrate;

[0029] S2, providing a protective film on the metal plate, and forming a blind hole on the metal plate by drilling, wherein the distance between the bottom of the blind hole and the insulating plate is 0 mm to 0.1 mm;

[0030] When the distance between the bottom of the blind hole and the insulating plate is 0 mm, step S3 can be skipped and step S4 can be directly entered; when the distance between the bottom of the blind hole and the insulating plate is greater than 0 mm and less than or equal to 0.1 mm, step S3 must be performed to remove the residue of the metal plate.

[0031] S3, removing part of the metal plate residue between the bottom of the blind hole and the insulating plate by a mechanical processing method to expose the insulating plate;

[0032] S4, removing the protective film on the metal plate surface, filling the blind hole with liquid insulating resin, and waiting for a certain period of time for the liquid insulating resin to solidify;

[0033] S5. Forming a through hole on the cured insulating resin by drilling process to obtain the substrate with insulating through hole as described above, wherein the geometric center of the cross section of the through hole is the same as that of the cross section of the blind hole, and the through hole is located in the blind hole.

[0034] Preferably, the mechanical processing method includes: laser ablation processing and etching processing.

[0035] The present invention also discloses an LED lighting module, comprising: a substrate with insulating through holes and an LED constant current drive circuit arranged on the substrate with insulating through holes, wherein the substrate with insulating through holes is the substrate with insulating through holes described in any of the above embodiments.

[0036] See also Figure 3 The LED constant current driving circuit includes: a filter module 10, a rectifier bridge 20, a primary clamp protection module 30, a current output module 40, a primary feedback control module 50, a delay module 60, a current sampling module 70 and a buffer module 80; the filter module 10 filters the current input from the rectifier bridge 20 and then inputs it into the primary clamp protection module 30, and the primary clamp protection module 30 outputs a constant current signal to the current output module 40 according to the signal received from the primary feedback control module 50; the primary feedback control module 50 compares the current feedback from the current output module 40 with the current collected by the current sampling module 70 and outputs a current signal to the primary clamp protection module 30, and the current sampling module 70 inputs the collected current of the buffer module into the primary clamp protection module 30 via the delay module 60. The LED constant current driving circuit uses only one primary feedback control module 50 to simplify the circuit structure while still having good constant current characteristics.

[0037] Preferably, the filtering module 10 includes: a first inductor L1, a first resistor R1, a first capacitor C1 and a second capacitor C2; the first inductor L1, the first resistor R1, the first capacitor C1 and the second capacitor C2 form a π-type filtering circuit; the first end of the first resistor R1 is connected to the input end of the rectifier bridge 20, and the second end of the first resistor R1 is connected to the primary clamping protection circuit; the first resistor R1 is connected in parallel with the first inductor L1; the first end of the first capacitor C1 is electrically connected to the first end of the first resistor R1, and the second end of the first capacitor C1 is grounded; the first end of the second capacitor C2 is electrically connected to the second end of the first resistor R1, and the second end of the second capacitor C2 is grounded.

[0038] Preferably, the primary clamping protection module 30 includes a second resistor R2, a third resistor R3, a third capacitor C3, a fourth resistor R4, a fifth resistor R5 and a first diode D1; the first end of the second resistor R2 is electrically connected to the second end of the first resistor R1, the second end of the second resistor R2 is connected to the first end of the third resistor R3, and the second end of the third resistor R3 is connected to the primary feedback control module 50; the first end of the third capacitor C3 is connected to the first end of the second resistor R2, the second end of the third capacitor C3 is connected to the first end of the fifth resistor R5, the fourth resistor R4 is connected in parallel with the third capacitor C3, the first end of the fourth resistor R4 is connected to the current output module 40, and the second end of the fourth capacitor C4 is connected to the first end of the fifth resistor R5; the second end of the fifth resistor R5 is electrically connected to the cathode of the first diode D1, and the anode of the first diode D1 is connected to the buffer module 80 and the current output module 40. The primary clamp protection circuit absorbs the leakage inductance peak voltage to protect the switch tube, and the fifth resistor R5 can reduce the temperature rise, improve the ability to suppress high-frequency ringing and suppress system electromagnetic interference. The resistance value of the fifth resistor R5 is less than 100Ω.

[0039] Preferably, the buffer module 80 includes: a first switch tube Q1, a sixth resistor R6, a seventh resistor R7 and a ninth capacitor C9; the first end of the first switch tube Q1 is connected to the positive electrode of the first diode D1, the second end of the first switch tube Q1 is connected to the current sampling module 70, and the third end of the first switch tube Q1 is connected to the first end of the sixth resistor R6 and the first end of the seventh resistor R7; the second end of the sixth resistor R6 is connected to the primary feedback control module 50, and the second end of the seventh resistor R7 is connected to the current sampling module 70 and the delay module 60; the ninth capacitor C9 is connected in parallel with the first switch tube Q1. The ninth capacitor C9 is connected in parallel at both ends of the first switch tube Q1, which can buffer the turn-off of the first switch tube Q1 to reduce the turn-off loss, and can also form resonance with the primary inductance of the transformer to help the recovery of the transformer core.

[0040] Preferably, the delay module 60 includes: an eighth resistor R8 and a fourth capacitor C4; the first end of the eighth resistor R8 is connected to the second end of the seventh resistor R7 and the current sampling module 70, the second end of the eighth resistor R8 is connected to the first end of the fourth capacitor C4 and the primary feedback control module 50; the first end of the fourth capacitor C4 is connected to the primary feedback control module 50, and the second end of the fourth capacitor C4 is grounded. In this embodiment, the eighth resistor R8 is used to weaken the current spike of the first switch tube Q1 to the current sampling module 70 during the switching process.

[0041] Preferably, the current sampling module 70 includes a ninth resistor R9 and a tenth resistor R10; the first end of the ninth resistor R9 is connected to the second end of the first switch tube Q1 and the first end of the eighth resistor R8, and the second end of the ninth resistor R9 is grounded; the tenth resistor R10 is connected to the ninth resistor R9 in parallel, the first end of the tenth resistor R10 is electrically connected to the first end of the eighth resistor R8, and the second end of the tenth resistor R10 is grounded.

[0042] Preferably, the primary feedback control module 50 includes a processor U1, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a second diode D2, a first transformer T2 and a tenth capacitor; the first pin OUT of the processor U1 is connected to the second end of the sixth resistor R6, the second pin Isense of the processor U1 is connected to the second end of the eighth resistor R8 and the first end of the fourth capacitor C4, the third pin GND of the processor U1 is grounded, the fourth pin Vcc of the processor U1 is connected to the first end of the eleventh resistor R11, the fifth pin Vsense of the processor U1 is connected to the first end of the fifth capacitor C5, the second end of the thirteenth resistor R13 and the first end of the fourteenth resistor R14; the sixth pin Vin of the processor U1 is connected to The first end of the sixth capacitor C6 is connected to the second end of the third resistor R3; the fourth pin Vcc pin of the processor U1 is connected to the first end of the seventh capacitor C7 and the second end of the twelfth resistor R12; the first end of the twelfth resistor R12 is connected to the cathode of the second diode D2; the second end of the twelfth resistor R12 is connected to the first end of the seventh capacitor C7; the first end of the thirteenth resistor R13 is connected to the anode of the second diode D2 and the current output module 40; the second end of the thirteenth resistor R13 is connected to the first end of the fourteenth resistor R14; the first end of the tenth capacitor is connected to the current output module 40; the second end of the eleventh resistor R11, the second end of the fifth capacitor C5, the second end of the sixth capacitor C6, the second end of the seventh capacitor C7, the second end of the tenth capacitor and the second end of the fourteenth resistor R14 are electrically connected. The fifth pin Vsense of the processor U1 is an auxiliary voltage sensor, and the auxiliary side voltage signal is obtained after the voltage is divided by the thirteenth resistor R13 and the fourteenth resistor R14: the fifth pin Vsenseo of the processor U1 detects voltage changes. If an error occurs, the first pin OUT of the processor U1 adjusts the duty cycle of the first switch tube Q1 to control the energy transmission of the first transformer T2 to maintain the voltage constant. The second pin Isense of the processor U1 is a primary current sensor, which periodically detects the primary peak current. The voltage on the ninth resistor R9 and the tenth resistor R10 is compared with the internal reference voltage of the chip. Once an error occurs, the processor U1 will adjust the duty cycle of the first switch tube Q1 to maintain the voltage constant. Among them, the ninth resistor R9 and the tenth resistor R10 are high-precision resistors with an error of 1%.

[0043] Preferably, the current output module 40 includes a second transformer T2, a third diode D3, an eighth capacitor C8 and a fifteenth resistor R15; one end of the second transformer T2 is connected to the first end of the fourth resistor R4; the other end of the second transformer T2 is connected to the positive electrode of the third diode D3; the negative electrode of the third diode D3 is connected to the first end of the eighth capacitor C8, and the second end of the eighth capacitor C8 is connected to the second transformer T2; the fifteenth resistor R15 is connected in parallel with the eighth capacitor C8.

[0044] In summary, the present invention provides a substrate with insulating through holes, a manufacturing method and an LED lighting module, wherein the substrate with insulating through holes comprises: a metal plate 11, an insulating plate 12, a copper foil circuit 13, a through hole 14, and an insulating member 15. The substrate has a simple structure and the metal plate 11 is low in cost. The manufacturing method of the substrate with insulating through holes first uses a laminated substrate to make insulating through holes, which is universal and does not require laminating of specially designed through holes for different products. At the same time, it also avoids the scraping, baking and wire drawing steps required for laminating after filling with insulating material. The manufacturing method is simple, the yield is high and the cost is low. At the same time, the LED lighting module uses an LED constant current drive circuit having a filter module 10, a rectifier bridge 20, a primary clamping protection module 30, a current output module 40, a primary feedback control module 50, a delay module 60, a current sampling module 70 and a buffer module 80 to drive the LED. The circuit structure is simple, the LED components are effectively protected, and the service life of the LED components is extended.

[0045] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A method for manufacturing an LED lighting module, characterized in that: The following steps are involved: S1. Provide pre-treated metal plates, insulating plates and copper foil circuits, and laminate the metal plates, insulating plates and copper foil circuits to produce LED lighting module substrates; S2, providing a protective film on the metal plate, and forming a blind hole on the metal plate by drilling, wherein the distance between the bottom of the blind hole and the insulating plate is 0 mm to 0.1 mm; S3, removing part of the metal plate residue between the bottom of the blind hole and the insulating plate by a mechanical processing method to expose the insulating plate; S4, removing the protective film on the metal plate surface, filling the blind hole with liquid insulating resin, and waiting for a certain period of time for the liquid insulating resin to solidify; S5, forming a through hole on the cured insulating resin by drilling to obtain a substrate with an insulating through hole, wherein the geometric center of the cross section of the through hole is the same as that of the cross section of the blind hole, and the through hole is located inside the blind hole; The substrate with insulating through-holes comprises: a metal plate, an insulating plate, a copper foil circuit, a through-hole, and an insulating member; the insulating plate is provided with a first contact surface and a second contact surface, the first contact surface is arranged opposite to the second contact surface, the metal plate is in contact with the first contact surface, the copper foil circuit is in contact with the second contact surface, the hole wall of the through-hole is composed of the insulating plate, the copper foil circuit and the insulating member, and the insulating member is detachably connected to the metal plate; The LED lighting module comprises: the substrate with the insulating through hole and an LED constant current driving circuit arranged on the substrate with the insulating through hole.

2. The method for manufacturing an LED lighting module according to claim 1, characterized in that: The mechanical processing method includes: laser ablation processing and etching processing.

3. The method for manufacturing an LED lighting module according to any one of claims 1 to 2, characterized in that: The metal plate is an aluminum plate, a copper plate or a metal alloy plate.

4. The method for manufacturing an LED lighting module according to claim 1, characterized in that: The LED constant current drive circuit includes: a filter module, a rectifier bridge, a primary clamp protection module, a current output module, a primary feedback control module, a delay module, a current sampling module and a buffer module; the filter module filters the current input by the rectifier bridge and inputs it into the primary clamp protection module; the primary clamp protection module outputs a constant current signal to the current output module according to the signal received from the primary feedback control module; the primary feedback control module compares the current feedback from the current output module with the current collected by the current sampling module and outputs a current signal to the primary clamp protection module; the current sampling module inputs the collected current of the buffer module into the primary clamp protection module via the delay module.

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