Base island structure of optocoupler lead frame

Abstract

The utility model relates to the technical field of optocoupler supports, in particular to a base island structure of an optocoupler lead frame. According to the utility model, the pressing block is arranged on the first substrate, so that in a wire welding process, when a pressing plate of wire welding equipment respectively presses the supporting legs and the pressing block which are fixed with the same first substrate, the limiting effect on the first substrate can be improved by increasing the contact area with the wire welding equipment; by further limiting the structure and the position of the pressing block, on one hand, the probability of electrical abnormality can be reduced, the safety and the stability of the finished optocoupler in the use process can be ensured, on the other hand, the stability of wire welding equipment when pressing the pressing block can be improved, and the production efficiency can be improved. Meanwhile, the fixing and limiting effects on the first substrate are improved through the pressed pressing blocks and the supporting feet, and the probability that the silver wires are broken in the wire welding process is further reduced; the problem that a silver wire is broken due to the fact that the base island is prone to shaking during wire welding due to the fact that the limiting force of the base island of the optocoupler support is insufficient during wire welding is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of optical coupling lead frames, in particular to a base island structure of an optical coupling lead frame. Background Art

[0002] When welding the optocoupler bracket, the object to be welded is generally silver wire, and the diameter of the silver wire is very small. Therefore, the silver wire has poor stress resistance and is prone to breakage during the welding process. The part connecting the two ends of the silver wire on the base island during welding is prone to shaking, which is one of the reasons for its breakage. Figure 1-Figure 3 As shown, in the prior art, it is necessary to use a pressure plate of the wire bonding equipment to press near the pins on the base island, or to press on the edge of the base island, so as to reduce the probability of shaking in the area connecting the two ends of the silver wire on the base island during wire bonding.

[0003] Since the area of ​​the base island on the optocoupler bracket is extremely small, during actual welding, the contact area between the pressure plate of the wire welding equipment and the base island area is very small, or there is no contact. Therefore, during actual wire welding, the base island may shake due to insufficient fixing force and other reasons such as vibration of the equipment, causing the silver wire to break during the welding process. Utility Model Content

[0004] In view of the deficiencies in the prior art, the utility model provides a base island structure of an optocoupler lead frame, which solves the problem that the base island is prone to shaking during wire welding and causes the silver wire to break due to insufficient limiting force of the base island of the optocoupler bracket during wire welding.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] A base island structure of an optical coupling lead frame includes two first substrates for solid crystal and two second substrates respectively cooperating with the two first substrates for wire bonding. The first substrate and the second substrate are both provided with supporting feet as conductors. The first substrate is provided with a pressing block for pressing a pressing plate of a wire bonding device.

[0007] Preferably, the pressing block is located on a side of the corresponding first substrate away from the other second substrate.

[0008] Preferably, the distance between the pressing block and the corresponding second substrate is greater than or equal to half of the thickness of the second substrate.

[0009] Preferably, the pressing block comprises a pressing portion arranged on the corresponding second substrate, a fan-shaped portion is arranged on a side of the pressing portion away from the corresponding second substrate, and both ends of the arcuate side of the fan-shaped portion are smoothly connected to the side edge of the pressing portion.

[0010] Preferably, the distance of the pressing block from a side close to the first substrate to a side far from the first substrate is greater than or equal to 0.1 mm.

[0011] Preferably, the pressing block is located on a side edge of the corresponding first substrate close to one end of the corresponding second substrate.

[0012] Compared with the prior art, the utility model provides a base island structure of an optical coupler lead frame, which has the following beneficial effects:

[0013] 1. The utility model arranges a pressing block on the first substrate. In the wire bonding process, when the pressing plate of the wire bonding device is pressed on the supporting feet and the pressing block fixed to the same first substrate respectively, the limiting effect on the first substrate can be improved by increasing the contact area with the wire bonding device, so that the first substrate can be made more stable during the wire bonding process, and the probability of the silver wire breaking due to the shaking of the first substrate during welding can be reduced.

[0014] 2. By further limiting the structure and position of the pressing block, on the one hand, the probability of electrical abnormalities can be reduced, ensuring the safety and stability of the finished optocoupler during use; on the other hand, the stability of the wire bonding equipment when pressing the pressing block can be improved. At the same time, the fixed limiting effect of the first substrate can be improved by the compressed pressing block and the support feet, further reducing the probability of silver wire breakage during the wire bonding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0016] Figure 1 This is a structural schematic diagram of a press plate of a wire welding device of the utility model;

[0017] Figure 2 This is a schematic diagram of the position of the wire bonding equipment pressure plate and the optical coupler bracket;

[0018] Figure 3 It is a schematic diagram of the location of the wire bonding equipment pressure plate and the existing optocoupler bracket base island;

[0019] Figure 4 It is a schematic diagram of the positions of the wire bonding equipment pressure plate and the base island of the optical coupling bracket of the utility model;

[0020] Figure 5 It is a schematic diagram of the base island of the optical coupling bracket of the utility model.

[0021] In the figure: 1, first substrate; 2, second substrate; 3, support foot; 4, pressing block; 41, pressing portion; 42, fan-shaped portion. DETAILED DESCRIPTION

[0022] The following will describe the implementation methods of the present application in detail with the help of accompanying drawings and examples, so that the implementation process of how the present application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0023] In order to reduce the breakage of silver wires caused by the shaking of the base island during the wire bonding process and improve the product qualification rate during the wire bonding process, the utility model provides a base island structure of an optocoupler lead frame. The structure of the base island is improved. Please refer to Figure 4-Figure 5 During welding, the contact area between the wire bonding equipment pressure plate and the base island is increased, thereby increasing the pressing force of the pressure plate on the base island, improving the stability of the base island during welding, and reducing the probability of silver wire breakage due to base island jitter. The base island structure includes two first substrates 1 for solid crystal, and two second substrates 2 respectively cooperated with the two first substrates 1 for wire bonding, that is, the two ends of the silver wire are respectively located on the first substrate 1 and the corresponding second substrate 2, and the first substrate 1 and the second substrate 2 are both provided with supporting feet 3 as conductors. The first substrate 1 is provided with a pressing block 4 for pressing the wire bonding equipment pressure plate, and the wire bonding equipment pressure plate is pressed on the pressing block 4 and the supporting feet 3, so that the pressing block 4 and the supporting feet 3 cooperate to fix the two position points of the first substrate 1, so that the first substrate 1 is more stable during wire bonding, and the probability of the silver wire breaking during welding due to shaking is reduced.

[0024] Theoretically, the position of the pressing block 4 can be located anywhere around the first substrate 1, but considering the structure of the optocoupler product itself and the position interference of parts on the device, the pressing block 4 is located on the side of the corresponding first substrate 1 away from the other second substrate 2. In this way, there is no need to modify the pressing plate of the existing device, and it can be pressed on the pressing block 4, which is more convenient.

[0025] When the distance between the pressing block 4 and the corresponding second substrate 2 is too small, since the two ends of the silver wire are respectively arranged on the second substrate 2 and the corresponding first substrate 1, when the distance between the two is too close, electrical abnormalities may occur due to the discharge phenomenon, so that the distance between the pressing block 4 and the corresponding second substrate 2 is greater than or equal to half of the thickness of the second substrate 2. For example, the thickness of the second substrate 2 currently used is 0.2 mm, and considering the processing error and other reasons, the actual distance between the pressing block 4 and the corresponding second substrate 2 is 0.2 mm, which can greatly reduce the probability of electrical abnormalities and ensure the safety of the finished optocoupler during use.

[0026] When there are sharp parts on the pressing block 4, for example, when the pressing block 4 is rectangular, the corners will cause a large concentration of charges and make the discharge intensity large. When the sharp part is close to the second substrate 2, electrical abnormalities may occur. Therefore, the pressing block 4 includes a clamping portion 41 arranged on the corresponding second substrate 2, and a fan-shaped portion 42 is arranged on the side of the clamping portion 41 away from the corresponding second substrate 2. The two ends of the arc edge of the fan-shaped portion 42 are smoothly connected to the side of the clamping portion 41. The fan-shaped portion 42 makes it easy for the upper side of the pressing block 4 to transition to the left, and when transitioning downward, it can be transitioned through a circular arc, so that the finished optocoupler is safer, and it is also convenient for stamping when producing the optocoupler bracket by stamping.

[0027] Since there may be an error in the relative position between the wire bonding equipment pressure plate and the pressure block 4, the wire bonding equipment pressure plate may be difficult to be stably pressed on the pressure block 4, so the distance from the side of the pressure block 4 close to the first substrate 1 to the side away from the first substrate 1 is greater than or equal to 0.1 mm to ensure the size of the pressure block 4, so that the wire bonding equipment pressure plate can be stably pressed on the pressure block 4, so that the pressed pressure block 4 and the corresponding support leg 3 cooperate to achieve the limitation of the corresponding first substrate 1, improve the stability of the first substrate 1 during wire bonding, and improve the welding yield.

[0028] When the pressing block 4 and the supporting foot 3 are respectively located on opposite sides of the first substrate 1, it is best to avoid shaking caused by lack of limit on one side of the first substrate 1. However, due to the limitation of the optical coupling structure, it is difficult for the pressing block 4 and the supporting foot 3 to be respectively located on opposite sides of the first substrate 1. Therefore, the pressing block 4 is located on the corresponding side of the first substrate 1 close to one end of the corresponding second substrate 2, so that the distance between the pressing block 4 and the supporting foot 3 can be maximized. The best position is to make the distance between the pressing block 4 and the corresponding second substrate 2 exactly half of the thickness of the second substrate 2, which can better fix the first substrate 1.

[0029] It should be noted that, in this article, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0030] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A base island structure of an optical coupling lead frame, comprising two first substrates (1) for die bonding, and two second substrates (2) respectively cooperating with the two first substrates (1) for wire bonding, wherein the first substrate (1) and the second substrate (2) are both provided with legs (3) as conductors, characterized in that: A pressing block (4) for pressing a pressing plate of a wire bonding device is provided on the first substrate (1).

2. The island structure according to claim 1, characterized in that: The pressing block (4) is located on a side of the corresponding first substrate (1) away from the other second substrate (2).

3. The island structure according to claim 1, characterized in that: The distance between the pressing block (4) and the second substrate (2) corresponding thereto is greater than or equal to half of the thickness of the second substrate (2).

4. The island structure according to claim 1, characterized in that: The pressing block (4) comprises a pressing portion (41) arranged on the corresponding second substrate (2), a fan-shaped portion (42) is arranged on the side of the pressing portion (41) away from the corresponding second substrate (2), and both ends of the arc-shaped edge of the fan-shaped portion (42) are smoothly connected to the side of the pressing portion (41).

5. The island structure according to claim 2, characterized in that: The distance of the pressing block (4) from the side close to the first substrate (1) to the side far from the first substrate (1) is greater than or equal to 0.1 mm.

6. The island structure according to claim 2, characterized in that: The pressing block (4) is located on the side of the corresponding first substrate (1) and close to one end of the corresponding second substrate (2).

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