Lead frame of photoelectric coupler

Abstract

The invention relates to a lead frame of a photoelectric coupler, the lead frame of the photoelectric coupler comprises a transverse rib unit, the transverse rib unit comprises a plurality of parallel transverse ribs, and each transverse rib is provided with a plurality of support nodes; the base island units are fixed on the transverse bars through the supporting nodes; the lead frame comprises a middle penetrating type connecting rib which is perpendicular to the transverse ribs and located at the bottoms of the middles of the transverse ribs so as to support the transverse ribs. According to the invention, the structural stability, the heat dissipation performance and the deformation resistance of the lead frame can be improved, so that the increasing production requirements of high-performance photoelectric couplers can be met.

Description

Technical Field

[0001] This invention relates to the field of optocoupler technology, and particularly to a lead frame for an optocoupler. Background Technology

[0002] In the field of electronics, optocouplers are important electronic components widely used in various circuit systems for signal transmission and isolation. The lead frame, as a key component of the optocoupler, directly affects the overall performance and reliability of the optocoupler through its structural design and performance.

[0003] Traditional optocoupler lead frames mostly employ a single-row structure, which has several limitations. Firstly, single-row lead frames have low resource utilization, leading to higher production costs. In actual production, to increase optocoupler output, the width and density of the lead frames are typically increased, but this approach causes a series of problems. For example, in the stamping and bending processes, excessively wide lead frames cannot effectively counteract the mechanical stress generated by stamping using only longitudinal connecting ribs, making the lead frames prone to curling and lateral bending deformation, thus affecting the accuracy of the packaging process. Furthermore, in the plastic encapsulation process of optocouplers, excessively wide lead frames increase lateral thermal resistance, hindering heat dissipation and exacerbating thermal stress accumulation, indirectly causing the lead frames to bulge and arch laterally. This deformation not only affects the positioning in subsequent punching processes, leading to problems such as misalignment and tool breakage, but may also cause a decrease in the insulation performance of the optocoupler, seriously affecting product quality and reliability. Furthermore, when placing the material box in the optocoupler manufacturing process, the finished lead frame is too wide and lacks support in the middle. Under the action of gravity, the support is prone to collapse, which affects the material feeding on the track during production, causing material collapse, lead frame deformation, and in severe cases, even material jamming and scrapping, resulting in significant production losses. Summary of the Invention

[0004] This invention provides a lead frame for an optocoupler, aiming to solve at least one of the technical problems existing in the prior art.

[0005] The technical solution of the present invention is a lead frame for an optocoupler, comprising: A horizontal rib unit consists of several parallel horizontal ribs, each with several support nodes. Several base island units, wherein the base island units are fixed to the transverse ribs via the support nodes; The lead frame includes a central through-type connecting rib, which is perpendicular to several horizontal ribs and located at the bottom of the middle part of the horizontal ribs to support the horizontal ribs.

[0006] According to some embodiments of the present invention, the lead frame further includes a first support outer frame and a second support outer frame, the first support outer frame being parallel to the central through-type connecting rib, the second support outer frame being parallel to the central through-type connecting rib, one end of the transverse rib being connected to the first support outer frame, and the other end of the transverse rib being connected to the second support outer frame.

[0007] According to some embodiments of the present invention, the lead frame is made of copper alloy and is connected to a pre-set chip and external circuit during the semiconductor packaging process.

[0008] According to some embodiments of the present invention, the chip is a light-emitting diode and a phototransistor.

[0009] According to some embodiments of the present invention, the external circuit is an external circuit of a transistor-type optocoupler. The external circuit of the transistor-type optocoupler includes a current source, a power supply voltage source, an input terminal, an output terminal, an input resistor, a light-emitting diode (LED), a phototransistor, and a pull-up resistor. The current source is connected to the positive terminal of the LED, the negative terminal of the LED is grounded through the input resistor, the input terminal is connected to a common node between the negative terminal of the LED and the input resistor, the power supply voltage source is connected to the collector of the phototransistor through the pull-up resistor, the emitter of the phototransistor is grounded, and the output terminal is connected to a common node between the power supply voltage source and the collector of the phototransistor.

[0010] According to some embodiments of the present invention, both the first bracket outer frame and the second bracket outer frame are provided with anti-fool holes.

[0011] According to some embodiments of the present invention, positioning holes are provided on both the first bracket outer frame and the second bracket outer frame.

[0012] According to some embodiments of the present invention, a first number of support nodes are provided on the transverse rib, the number of base island units is the same as the number of support nodes, and the number of base island units located on the upper side of the central through-type connecting rib is the same as the number of base island units located on the lower side of the central through-type connecting rib.

[0013] According to some embodiments of the present invention, the lead frame has a length of 238.7 mm, a width of 73.51 mm, and a thickness of 0.2 mm, and the spacing between two adjacent transverse ribs in the lead frame is 10.85 mm.

[0014] According to some embodiments of the present invention, the material of the central through-type connecting rib is C194 copper or SPEC iron.

[0015] The lead frame of the optocoupler provided in this embodiment of the invention has at least one of the following advantages or beneficial effects: the lead frame includes a central through-type connecting rib, which is perpendicular to the horizontal rib and located at the bottom of the middle of the horizontal rib. The main function of the central through-type connecting rib is to support the horizontal rib and enhance the structural stability of the entire lead frame. By setting the connecting rib at the bottom of the middle of the horizontal rib, bending or deformation of the horizontal rib during use can be effectively prevented, thereby ensuring the overall performance and reliability of the optocoupler. In addition, the central through-type connecting rib being located at the bottom of the middle of the horizontal rib allows for maximum space utilization while providing optimal support.

[0016] Through a combination of horizontal ribs, support nodes, and a central through-type connecting rib, the entire lead frame exhibits high structural stability, capable of withstanding certain mechanical stresses and ensuring the reliability of the optocoupler under various operating environments. The support node design allows the base island unit to be precisely fixed to the horizontal ribs, ensuring the accurate positioning of the chip and other electronic components, which is crucial for the performance of the optocoupler. The central through-type connecting rib provides support while optimizing space utilization, enabling the lead frame to achieve optimal structural performance within a limited space. This optocoupler lead frame, through its rational structural layout and material selection, ensures high performance and high reliability for the optocoupler.

[0017] Furthermore, additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the curling of a conventional lead frame provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the side bending of a conventional lead frame after stamping, provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the conventional lead frame after plastic sealing and horizontal bending provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the collapse failure of the conventional lead frame base island provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the overall structure of the lead frame of the optocoupler provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the lead frame and the direction of providing support force and the direction of dissipating thermal stress of the optocoupler provided in the embodiment of the present invention; Figure 7 This is a detailed structural diagram of the first type of lead frame of the optocoupler provided in the embodiment of the present invention; Figure 8 is a circuit diagram of the external circuit provided in an embodiment of the present invention; Figure 9 This is a detailed view of the second structure of the lead frame of the optocoupler provided in the embodiment of the present invention; Figure 10 This is a schematic diagram of the structure of a conventional lead frame provided in an embodiment of the present invention.

[0019] The above figures include the following reference numerals: 100, horizontal rib; 200, base island unit; 300, lead frame; 310, central through-type connecting rib; 320, outer frame of the first support; 330, outer frame of the second support; 340, anti-fool hole; 350, positioning hole. Detailed Implementation

[0020] The following will provide a clear and complete description of the concept, specific structure, and technical effects of the present invention in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, solution, and effects of the present invention. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0021] It should be noted that, unless otherwise specified, when a feature is referred to as "fixed" or "connected" to another feature, it can be directly fixed or connected to the other feature, or indirectly fixed or connected to the other feature. Furthermore, the descriptions of "upper," "lower," "left," "right," "top," and "bottom" used in this invention are only relative to the relative positional relationships of the various components of the invention in the accompanying drawings.

[0022] Furthermore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this specification is for the purpose of describing particular embodiments only and not for limiting the invention. The term "and / or" as used herein includes any combination of one or more of the associated listed items.

[0023] It should be understood that although the terms first, second, third, etc., may be used to describe various elements in this invention, these elements should not be limited to these terms. These terms are only used to distinguish elements of the same type from each other. For example, a first element may also be referred to as a second element without departing from the scope of this invention, and similarly, a second element may also be referred to as a first element.

[0024] In related technologies, lead frames are currently the main raw material for manufacturing electronic components, primarily used in the production of optocouplers. Since most lead frames used are single-row, they are costly, have low resource utilization, and are inefficient, resulting in significant production losses. Increasing the width and density of the lead frames to improve the output of single-chip optocouplers would lead to the following problems: Reference Figure 1and Figure 2 As shown, during the stamping and bending production of the lead frame, due to the excessively large roll width, the longitudinal connecting ribs alone cannot resist the mechanical stress generated by stamping, which causes the lead frame to be prone to curling and lateral bending deformation, thereby affecting the packaging process accuracy.

[0025] Reference Figure 3 As shown, during the encapsulation of optocouplers, if the width of the finished lead frame is too large, the excessively wide lead frame will increase the lateral thermal resistance, hinder heat dissipation and aggravate the accumulation of thermal stress, indirectly causing the lead frame to bend and arch. In severe cases, it may even affect the positioning of subsequent punching processes, leading to problems such as cutting deviation and tool breakage.

[0026] When placing the material box in the optocoupler manufacturing process, refer to... Figure 4 As shown, due to the excessive width of the finished lead frame, the middle part of the lead frame will lack support and the weight will cause the support to collapse, affecting the material feeding on the track during production. This can lead to material collapse, lead frame deformation, and in severe cases, even material jamming and scrapping, as well as affecting the insulation performance of the optocoupler.

[0027] Based on this, embodiments of the present invention provide a lead frame for an optocoupler, which is beneficial to improving the structural stability, heat dissipation performance and deformation resistance of the lead frame, so as to meet the growing production demand for high-performance optocouplers.

[0028] Reference Figure 5 As shown, Figure 5 This is a schematic diagram of the overall structure of the lead frame of the optocoupler provided in an embodiment of the present invention. The lead frame of the optocoupler includes a horizontal rib 100 unit, a plurality of base island units 200, and a lead frame 300. The horizontal rib 100 unit includes a plurality of parallel horizontal ribs 100, and each horizontal rib 100 is provided with a plurality of support nodes. The plurality of base island units 200 are fixed to the horizontal ribs 100 by a plurality of support nodes. The lead frame 300 includes a central through-type connecting rib 310, which is perpendicular to the plurality of horizontal ribs 100 and located at the bottom of the middle part of the horizontal ribs 100 to support the horizontal ribs 100.

[0029] In this embodiment of the invention, the horizontal rib 100 unit is composed of several parallel horizontal ribs 100. Each horizontal rib 100 is provided with several support nodes. These support nodes are used to fix the base island unit 200, ensuring the stability and precise position of the base island unit 200 on the horizontal rib 100. The horizontal rib 100 unit serves to support and fix the base island unit 200, while also providing structural stability for the lead frame 300. Several base island units 200 are fixed to the horizontal ribs 100 by several support nodes. The base island unit 200 is the part in the optocoupler used to fix the chip and other electronic components. By fixing the base island unit 200 to the support nodes of the horizontal rib 100, the stability and precise position of the chip and other components in the lead frame 300 can be ensured. The base island unit 200 is usually connected to the support nodes by welding or other mechanical fixing methods to ensure its firmness on the horizontal rib 100.

[0030] The lead frame 300 includes a central through-type connecting rib 310, which is perpendicular to the horizontal rib 100 and located at the bottom center of the horizontal rib 100. The main function of the central through-type connecting rib 310 is to support the horizontal rib 100 and enhance the structural stability of the entire lead frame 300. By setting the connecting rib at the bottom center of the horizontal rib 100, bending or deformation during use can be effectively prevented, thereby ensuring the overall performance and reliability of the optocoupler. In addition, the central through-type connecting rib 310 is located at the bottom center of the horizontal rib 100, which maximizes space utilization while providing optimal support.

[0031] Through the combined design of the horizontal ribs 100, support nodes, and central through-type connecting ribs 310, the entire lead frame 300 exhibits high structural stability, capable of withstanding certain mechanical stresses and ensuring the reliability of the optocoupler under various operating environments. The design of the support nodes allows the base island unit 200 to be precisely fixed to the horizontal ribs 100, thereby ensuring the accurate positioning of the chip and other electronic components, which is crucial for the performance of the optocoupler. The design of the central through-type connecting ribs 310 provides support while optimizing space utilization, enabling the lead frame 300 to achieve optimal structural performance within a limited space. This optocoupler lead frame, through its rational structural layout and material selection, ensures the high performance and high reliability of the optocoupler.

[0032] In this embodiment of the invention, reference is made to Figure 6 As shown, Figure 6This is a schematic diagram of the lead frame and supporting force direction and thermal stress dissipation direction of the optocoupler provided in this embodiment of the invention. By adding a through-type connecting rib in the middle, the internal stress generated by the difference in thermal expansion coefficients of the lead frame 300 during the molding process (high temperature 150~200℃) can be effectively dispersed, reducing the risk of local thermal stress accumulation. The through-type connecting rib 310 in the middle serves as a stress transmission path, which can balance the expansion difference between the base island and the molding compound, reducing the probability of the lead frame 300 curling and arching.

[0033] The tensioning effect of the central through-type connecting rib 310 can offset the shrinkage stress generated by the cooling process after the plastic sealant has cured, and prevent the lead frame 300 from curling, warping, or twisting due to uneven shrinkage.

[0034] The central through-type connecting rib 310 enhances the overall rigidity of the lead frame 300, which can resist external mechanical forces (such as gravity collapse, external collision, and transportation vibration), reduce the deformation or unevenness of the lead frame 300, and is especially suitable for high-density packaging scenarios with wide lead frames 300.

[0035] The central through-type connecting rib 310 can reduce the deformation of the lead frame 300 during etching or stamping, and the transverse connecting rib can resist the mechanical stress generated by stamping, thus improving the problem of curling and side bending deformation of the lead frame 300.

[0036] Reference Figure 7 As shown, Figure 7 This is a detailed structural diagram of the first type of lead frame of the optocoupler provided in the embodiments of the present invention. In some embodiments, the lead frame 300 further includes a first support outer frame 320 and a second support outer frame 330. The first support outer frame 320 is parallel to the central through-type connecting rib 310, and the second support outer frame 330 is parallel to the central through-type connecting rib 310. One end of the horizontal rib 100 is connected to the first support outer frame 320, and the other end of the horizontal rib 100 is connected to the second support outer frame 330.

[0037] Understandably, the lead frame 300 also includes a first support outer frame 320 and a second support outer frame 330. The first support outer frame 320 is parallel to the central through-type connecting rib 310 and is used to connect one end of the horizontal rib 100. The second support outer frame 330 is parallel to the central through-type connecting rib 310 and is used to connect the other end of the horizontal rib 100. Both the first support outer frame 320 and the second support outer frame 330 are parallel to the central through-type connecting rib 310.

[0038] Supported by the first bracket outer frame 320 and the second bracket outer frame 330, the two ends of the horizontal rib 100 are fixed, significantly improving the stability of the entire lead frame 300. The first bracket outer frame 320 and the second bracket outer frame 330 provide additional support for the horizontal rib 100. The two ends of the horizontal rib 100 are fixed to the bracket outer frame, ensuring the precise positioning of the horizontal rib 100 and preventing displacement or deformation during use. This ensures the precise positioning of the base island unit 200 and other components such as the chip, and prevents displacement or deformation of the horizontal rib 100 during use. This design makes the lead frame 300 more robust and the connections between components tighter, thereby improving the reliability and performance of the entire optocoupler.

[0039] In some embodiments of the present invention, the lead frame 300 is made of copper alloy and is connected to a pre-set chip and external circuit during the semiconductor packaging process.

[0040] The lead frame 300 is made of copper alloy. Copper alloy has excellent electrical conductivity, which effectively reduces resistance and ensures efficient current transmission. Copper alloy also has good thermal conductivity, allowing for rapid heat dissipation from the chip and improving the heat dissipation performance of the optocoupler. Copper alloy possesses high mechanical strength and toughness, capable of withstanding certain mechanical stresses, ensuring the stability and reliability of the lead frame 300 during the packaging process. Copper alloy is easy to process and can be formed into complex shapes through stamping, etching, and other processes to meet different design requirements. Copper alloy has good solderability, facilitating soldering connections with chips and other electronic components.

[0041] In the semiconductor packaging process, the lead frame 300 is connected to a pre-designed chip, typically using gold wire (gold wire bonding) or copper wire (copper wire bonding) to connect the chip's electrodes to the pins of the lead frame 300. Using gold wire to connect the chip's electrodes to the pins of the lead frame 300 offers advantages such as good conductivity and oxidation resistance. Alternatively, copper wire can be used, as it is less expensive and has good conductivity.

[0042] The pins of the leadframe 300 are also connected to external circuits. Typically, the pins of the leadframe 300 are connected to pads on a printed circuit board (PCB) via soldering or other connection methods to achieve electrical connection between the optocoupler and the external circuit. After connection, encapsulation, such as plastic or ceramic encapsulation, is performed to protect the chip and leadframe 300 from external environmental influences such as humidity, dust, and mechanical shock.

[0043] In this embodiment of the invention, the lead frame 300 is made of copper alloy and is connected to the pre-set chip and external circuitry during the semiconductor packaging process. This design fully utilizes the excellent properties of copper alloy, ensuring the high performance, high reliability, and good heat dissipation of the optocoupler, making it suitable for a variety of high-end applications.

[0044] In some embodiments of the present invention, the chip comprises a light-emitting diode (LED) and a phototransistor. The LED is located at the input terminal of the optocoupler, converting the input electrical signal into an optical signal, while the phototransistor is located at the output terminal of the optocoupler, converting the optical signal into an electrical signal.

[0045] When current flows through the input circuit, it causes the LED to emit light. The light signal emitted by the LED propagates through the encapsulation material (usually transparent plastic or glass) to the phototransistor. The light signal travels through the encapsulation material and reaches the photosensitive area of ​​the phototransistor. Upon receiving the light signal, the photosensitive area of ​​the phototransistor generates a photoelectric effect, turning the phototransistor on. Once the phototransistor is on, current is allowed to flow through the output circuit. By detecting changes in the current or voltage at the output, signal transmission and isolation can be achieved.

[0046] Optocouplers transmit optical signals and achieve electrical isolation between the input and output terminals, effectively preventing the influence of high voltage or noise at the input terminal on the output terminal. The copper alloy lead frame 300 provides excellent mechanical support and electrical connection, ensuring the high reliability of the optocoupler.

[0047] In one embodiment, the specific steps for connecting the lead frame 300 to the preset chips (light-emitting diode and phototransistor) during the semiconductor packaging process are as follows: Chip fixing: The light-emitting diode and the phototransistor are fixed on the base island unit 200 of the lead frame 300, usually by soldering or bonding.

[0048] Electrical connection: The electrodes of the light-emitting diodes and phototransistors are connected to the pins of the lead frame 300 using gold or copper wire to achieve electrical connection.

[0049] Packaging: The entire structure is encapsulated in a transparent plastic or glass encapsulation material to ensure that the transmission of optical signals is not affected by the external environment. The encapsulation material typically has good insulation and optical transparency to protect the chip and lead frame 300 from the influence of the external environment.

[0050] The lead frame 300 connects to the chip during semiconductor packaging, providing both mechanical support and electrical connection via a copper alloy lead frame 300. This design fully utilizes the excellent properties of copper alloy, ensuring high performance, high reliability, and good heat dissipation of the optocoupler.

[0051] Reference Figure 8 As shown in Figure 8, it is a circuit diagram of the external circuit provided in an embodiment of the present invention. In some embodiments of the present invention, the external circuit is an external circuit of a transistor-type optocoupler. The external circuit of the transistor-type optocoupler includes a current source, a power supply voltage source, an input terminal, an output terminal, an input resistor, a light-emitting diode (LED), a phototransistor, and a pull-up resistor. The current source and the positive terminal of the LED are connected. The negative terminal of the LED is grounded through the input resistor. The input terminal is connected to the common node between the negative terminal of the LED and the input resistor. The power supply voltage source is connected to the collector of the phototransistor through the pull-up resistor. The emitter of the phototransistor is grounded. The output terminal is connected to the common node between the power supply voltage source and the collector of the phototransistor.

[0052] In the external circuit, a current source provides a stable current to drive the LED, and a power supply voltage source provides the power supply voltage to drive the phototransistor and pull-up resistor. The input terminal receives the input signal, and the output terminal outputs the converted signal. The input resistor limits the current through the LED, protecting it from overcurrent damage. The LED converts the input electrical signal into a light signal. The phototransistor converts the light signal into an electrical signal. The pull-up resistor ensures that the output terminal provides a high level when the phototransistor is off.

[0053] In one embodiment, when a high-level signal is received at the input terminal, current flows through the input resistor to the LED, causing the LED to emit light. When a low-level signal is received at the input terminal, the LED does not emit light. The light signal emitted by the LED propagates through the encapsulation material to the photosensitive area of ​​the phototransistor. Upon receiving the light signal, the phototransistor generates a photoelectric effect, turning on the phototransistor. When the phototransistor is on, current flows through the pull-up resistor to the power supply voltage source, resulting in a low-level output. When the phototransistor is off, the pull-up resistor pulls the output high, resulting in a high-level output.

[0054] By transmitting optical signals, electrical isolation between the input and output terminals is achieved, effectively preventing the influence of high voltage or noise at the input terminal on the output terminal. The circuit design is simple, and the connections between components are clearly defined, ensuring the high reliability of the optocoupler. The low power consumption of light-emitting diodes gives the optocoupler an advantage in low-power applications. The extremely high transmission speed of optical signals enables the optocoupler to achieve rapid signal transmission.

[0055] Specifically, such as Figure 8 As shown, in the external circuit of a transistor-type optocoupler, Forward input current IF: The forward input current to the LED terminal, which is used to make the LED terminal conduct in the forward direction; Input resistor RIN: Current-limiting resistor at the LED terminal, used to adjust the LED; VCC: The power supply voltage at the output terminal of the phototransistor; Current source IC: Output current from the phototransistor; Pull-up resistor RL: The pull-up resistor at the end of the phototransistor is used to forward bias the phototransistor and adjust the output current of the phototransistor.

[0056] Reference Figure 9 As shown, Figure 9 This is a detailed view of the second structure of the lead frame of the optocoupler provided in the embodiment of the present invention. In some embodiments of the present invention, anti-fool holes 340 are provided on both the first bracket outer frame 320 and the second bracket outer frame 330.

[0057] By providing anti-mistake holes 340 in the first bracket outer frame 320 and the second bracket outer frame 330, it is ensured that the lead frame 300 will not be incorrectly inserted or placed in the wrong direction during assembly, effectively preventing directional errors during assembly. It also ensures that the lead frame 300 can be correctly aligned and fixed in the predetermined position during assembly, effectively preventing positional errors during assembly. Furthermore, during manual assembly, the anti-mistake holes 340 can serve as visual and tactile cues, helping operators quickly identify the correct orientation and position of the lead frame 300. This design can significantly reduce human error, improve assembly quality and efficiency, and reduce rework and scrap rates.

[0058] In some embodiments of the present invention, positioning holes 350 are provided on both the first bracket outer frame 320 and the second bracket outer frame 330. By providing positioning holes 350 on the first bracket outer frame 320 and the second bracket outer frame 330, it is ensured that the lead frame 300 can be accurately aligned with other components, such as chips and package shells, during assembly, achieving precise alignment. In conjunction with positioning pins or other fixing devices, it ensures that the lead frame 300 remains stable during assembly, preventing displacement and achieving positional fixation. By reducing alignment and adjustment time, the efficiency of the assembly process can be significantly improved, while ensuring that the lead frame 300 will not cause poor electrical connections or other problems due to positional deviations during assembly, thus improving reliability. During manual assembly, the positioning holes 350 can serve as visual and tactile cues, helping operators quickly identify the correct position of the lead frame 300. This design can significantly reduce human error and improve assembly quality.

[0059] In some embodiments of the present invention, a first number of support nodes are provided on the transverse rib 100, the number of base island units 200 is the same as the number of support nodes, and the number of base island units 200 located on the upper side of the central through-type connecting rib 310 is the same as the number of base island units 200 located on the lower side of the central through-type connecting rib 310.

[0060] A first number of support nodes are provided on the horizontal rib 100. These support nodes are used to fix the base island unit 200. The number of support nodes is the same as the number of base island units 200. Each base island unit 200 is fixed on a support node to ensure that each base island unit 200 has stable support. This design can ensure the precise layout of the base island units 200 on the horizontal rib 100 and improve the accuracy and efficiency of assembly.

[0061] The number of base island units 200 located on the upper side of the central through-type connecting rib 310 is the same as the number of base island units 200 located on the lower side of the central through-type connecting rib 310. This symmetrical distribution ensures that the weight and stress distribution of the lead frame 300 is uniform on both the upper and lower sides of the central through-type connecting rib 310, improving the overall balance and stability. The symmetrical distribution also helps to distribute heat evenly, preventing localized overheating and improving heat dissipation performance; symmetrical distribution can also reduce electrical signal asymmetry, improving the stability and reliability of signal transmission. This design significantly improves the stability and reliability of the lead frame 300 by ensuring symmetry and precise layout.

[0062] In some embodiments of the present invention, the lead frame 300 has a length of 238.7 mm, a width of 73.51 mm, and a thickness of 0.2 mm, and the step distance between two adjacent transverse ribs 100 in the lead frame 300 is 10.85 mm.

[0063] The length and width of the lead frame 300 need to match the dimensions of the package housing to ensure proper installation and fixation during the packaging process. A reasonable length and width maximize the use of the package space and increase package density. Preferably, in this embodiment of the invention, the lead frame 300 is set to a length of 238.7 mm and a width of 73.51 mm, providing a reasonable layout and heat dissipation performance. The lead frame 300 is set to a thickness of 0.2 mm. This thickness ensures mechanical strength while maintaining a thin and lightweight design. A thinner thickness helps improve heat dissipation performance, but the thermal conductivity of the material must be ensured.

[0064] The step distance refers to the center distance between two adjacent horizontal ribs 100. This parameter is crucial for ensuring a proper layout of the base island unit 200 and the chip. The step distance between two adjacent horizontal ribs 100 in the lead frame 300 is 10.85 mm. This 10.85 mm step distance is necessary to ensure electrical isolation between the base island unit 200 and the chip, while providing sufficient space for electrical connections.

[0065] In some embodiments of the present invention, the material of the central through-type connecting rib 310 is C194 copper or SPEC iron.

[0066] The central through-type connecting rib 310 is made of C194 copper. C194 copper has very high conductivity, which can effectively reduce resistance and ensure efficient current transmission. C194 copper has excellent thermal conductivity, which can quickly conduct heat away, helping to improve the heat dissipation performance of the optocoupler. C194 copper has high mechanical strength and toughness, which can withstand a certain amount of mechanical stress and ensure the stability of the lead frame 300 during use. C194 copper has good welding performance, which facilitates welding connections with chips and other electronic components. C194 copper has good corrosion resistance, which can resist chemical corrosion in the environment to a certain extent.

[0067] SPEC metal possesses high mechanical strength, enabling it to withstand significant mechanical stress. It also exhibits good magnetic properties, making it suitable for applications requiring magnetic support or shielding. Furthermore, SPEC metal is easy to process, allowing it to be molded into complex shapes through stamping, cutting, and other techniques to meet diverse design needs. Finally, SPEC metal is relatively inexpensive, making it suitable for mass production and cost-sensitive applications.

[0068] Therefore, the material for the central through-type connecting rib 310 can be either C194 copper or SPEC iron, depending on the application requirements. C194 copper has high electrical and thermal conductivity and good mechanical properties, making it suitable for high-performance and high-heat-dissipation applications. SPEC iron has high mechanical strength and good machinability, making it suitable for high-strength support and cost-sensitive applications.

[0069] In summary, referring to Figure 9 As shown, this invention provides a novel lead frame for a through-type high-density optocoupler with continuous ribs, which is related to... Figure 10 Compared to the conventional lead frame shown, the biggest difference is the addition of a through-type central connecting rib. The outer frame of the lead frame 300 provides edge support, and the individual base island units 200 are connected together by horizontal ribs 100. A central through-type connecting rib 310 is inserted in the middle of the support, as shown in the reference. Figure 9 As shown, the overall structure is "outer frame - horizontal rib 100 - single base island unit 200*8 - central connecting rib - single base island unit 200*8 - outer frame".

[0070] Understandably, the central through-type connecting rib 310 provides multi-node support for the lead frame 300. Its mechanical strength allows for a higher density layout, increasing the optocoupler density of a single lead frame 300, saving waste material after punching the lead frame 300, and significantly reducing material costs and associated manufacturing costs. Furthermore, the increased density of the single lead frame 300 reduces the loading and unloading time of the machine during operation, thereby increasing output and improving the human-machine ratio and work efficiency.

[0071] Specifically, in one embodiment, Material density = (width of lead frame 300 * length of lead frame 300) / number of base island units 200 The density of the high-density support material in this embodiment of the invention is 17546.8 mm² / 352 pcs = 49.849 mm² / pcs The density of a standard lead frame material is 7641.04 mm² / 120 pcs = 63.675 mm² / pcs The percentage increase in layout density = (layout density before change - layout density after change) / layout density before change * 100% = (63.675 - 49.849) / 63.675 * 100% = 21.72% Therefore, based on the above data, in this embodiment of the invention, the central through-type connecting rib provides multi-node support for the lead frame, and its mechanical strength allows for a higher density layout, which can improve the optical coupling density of a single lead frame.

[0072] The above description is merely a preferred embodiment of the present invention. The present invention is not limited to the above-described embodiments. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention, as long as they achieve the same technical effects, should be included within the scope of protection of the present invention. Within the scope of protection of the present invention, the technical solutions and / or implementation methods can have various modifications and variations.

Claims

1. A lead frame for an optocoupler, characterized in that, include: The horizontal rib (100) unit includes several parallel horizontal ribs (100), and each horizontal rib (100) is provided with several support nodes; Several base island units (200) are fixed to the transverse ribs (100) via the support nodes; The lead frame (300) includes a central through-type connecting rib (310), which is perpendicular to a plurality of transverse ribs (100) and located at the bottom of the middle part of the transverse ribs (100) to support the transverse ribs (100).

2. The lead frame of the optocoupler according to claim 1, characterized in that, The lead frame (300) further includes a first support frame (320) and a second support frame (330). The first support frame (320) is parallel to the central through-type connecting rib (310), and the second support frame (330) is parallel to the central through-type connecting rib (310). One end of the horizontal rib (100) is connected to the first support frame (320), and the other end of the horizontal rib (100) is connected to the second support frame (330).

3. The lead frame of the optocoupler according to claim 1, characterized in that, The lead frame (300) is made of copper alloy and is connected to the pre-set chip and external circuit during the semiconductor packaging process.

4. The lead frame of the optocoupler according to claim 3, characterized in that, The chip consists of a light-emitting diode and a phototransistor.

5. The lead frame of the optocoupler according to claim 3, characterized in that, The external circuit is a transistor-type optocoupler external circuit, which includes a current source, a power supply voltage source, an input terminal, an output terminal, an input resistor, a light-emitting diode (LED), a phototransistor, and a pull-up resistor. The current source is connected to the positive terminal of the LED, the negative terminal of the LED is grounded through the input resistor, the input terminal is connected to the common node between the negative terminal of the LED and the input resistor, the power supply voltage source is connected to the collector of the phototransistor through the pull-up resistor, the emitter of the phototransistor is grounded, and the output terminal is connected to the common node between the power supply voltage source and the collector of the phototransistor.

6. The lead frame of the optocoupler according to claim 2, characterized in that, Both the first bracket outer frame (320) and the second bracket outer frame (330) are provided with anti-fool holes (340).

7. The lead frame of the optocoupler according to claim 2, characterized in that, Positioning holes (350) are provided on both the first bracket outer frame (320) and the second bracket outer frame (330).

8. The lead frame of the optocoupler according to claim 1, characterized in that, The transverse rib (100) is provided with a first number of support nodes, the number of base island units (200) is the same as the number of support nodes, and the number of base island units (200) located on the upper side of the central through-type connecting rib (310) is the same as the number of base island units (200) located on the lower side of the central through-type connecting rib (310).

9. The lead frame of the optocoupler according to claim 1, characterized in that, The lead frame (300) has a length of 238.7 mm, a width of 73.51 mm, and a thickness of 0.2 mm. The step distance between two adjacent horizontal ribs (100) in the lead frame (300) is 10.85 mm.

10. The lead frame of the optocoupler according to claim 1, characterized in that, The material of the central through-type connecting rib (310) is C194 copper or SPEC iron.

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