CN108925035A - A kind of printed circuit board encapsulation design method and system based on 0402 encapsulation - Google Patents

Abstract

The invention discloses a kind of printed circuit boards based on 0402 encapsulation to encapsulate design method, includes the following steps：Pad design by 0402 encapsulation is octagonal shape；The center lead pin pitch for 2 pads that adaptation 0402 encapsulates；By 2 pads silk-screen circle rectangularity of 0402 encapsulation；Engineering confirmation is carried out to the layout board card using 0402 encapsulation；PCB design is carried out using the method at crawl pin center.The invention also discloses a kind of printed circuit board package design systems based on 0402 encapsulation.The method and system provided according to the present invention, the pin that the positive BGA package of PCB encapsulation and reverse side 0402 are encapsulated are completely overlapped；PCB placement-and-routing design area is extended, is all improved a lot to the functionality of entire board, reliability aspect；Substantially increase the design efficiency of PCB design.

Description

A printed circuit board package design method and system based on 0402 package

technical field

The present invention relates to the technical field of surface mount electronic component packaging, and more specifically, to a printed circuit board packaging design method and system based on 0402 packaging.

Background technique

In the development and design of printed circuit board (PCB) boards, the design of high-density boards is more and more involved in product development, and the chip integration level used is also getting higher and higher. Many small-pitch packages are used It is widely used in the design of electronic products, most of which are Ball Grid Array (BGA) packages. At present, the BGA chip package with a pitch value of 1.0mm has been widely used, and the usage rate is very high. At the same time, the BGA chip also contains many configuration circuits and power supply bypasses, which are usually required to be placed around or on the back of the BGA, and 0402 package resistors and capacitors are widely used. This kind of high-density board is a difficult problem that must be overcome in PCB layout.

The form of the BGA package on the PCB is a circular pad arranged in a matrix, and the diameter of the pad is usually set to 20mil (about 0.5mm (mm)), where mil is the length unit of the PCB or chip layout, 1mil = one thousandth of an inch. A pitch value of 1.0mm means that the center-to-center distance between each adjacent circular pad is 1.0mm (39.37mil). The appearance of the 0402 type package on the PCB is two rectangular pads, which are circled by silk screen to form a rectangle. The actual size of the 0402 type package is a rectangular ceramic chip electrical device with a length of 40mil (about 1.0mm) and a width of 20mil (about 0.5mm). The BGA package needs to punch out the pins (pins) during PCB wiring. At the same time, considering the cost issue, the traditional via design is generally used. After the via holes are occupied, the space on the back of the BGA package for device layout is very limited, requiring designers to spend more time and energy in designing the layout, and the expected electrical effect cannot be achieved. Therefore, according to the size data analysis of the 1.0mm BGA package and the 0402 type package, we can design a PCB package (footprint) that is completely suitable for the 0402 package of the BGA with a pitch of 1.0mm.

In view of the low design efficiency in the existing technology, wiring design engineers need to spend a lot of time wiring, and because the layout and wiring space is limited, the layout and wiring of many key signals cannot meet the design requirements and affect the performance of the entire board. At present, there is no effective solution. Program.

Contents of the invention

In view of this, the purpose of the embodiment of the present invention is to propose a printed circuit board package design method and system based on the 0402 package, which can completely overlap the pins of the front BGA package and the back 0402 package of the PCB package without the need for the set The BGA vias are rearranged, and the PCB layout and wiring design area is expanded without increasing the PCB board frame. At the same time, this technology can realize all 0402 package type configuration circuits and power supply bypasses of BGA chips to be placed nearby. The back of the BGA has greatly improved the functionality and reliability of the entire board.

Based on the above purpose, an aspect of the embodiment of the present invention provides a printed circuit board package design method based on 0402 package, including the following steps:

The pads of the 0402 package are designed in an octagonal shape;

Adaptively modify the center pin spacing of the two pads of the 0402 package;

circle the two pads of the 0402 package into a rectangular shape with silk screen printing;

The design board with 0402 package will be used for engineering confirmation;

Printed circuit board design using the method of grabbing the center of the pin.

In some embodiments, designing the pads of the 0402 package into an octagonal shape includes: using printed circuit board package design software to change the square pads of the 0402 package into a regular octagonal shape with an inscribed circle diameter of 24 mils.

In some embodiments, the adaptive modification of the central pin spacing of the 2 pads of the 0402 package includes: adapting the distance between the pins of the 2 adjacent BGA pads to the center of the 2 pads of the 0402 package The pin spacing is set to a spacing value of 1.0mm.

In some implementation manners, forming the two pads of the 0402 package into a rectangular shape with silkscreen includes: drawing the silkscreen on the 0402 package with a distance of 3 mils from the pads in the 0402 package.

In some embodiments, enclosing the two pads of the 0402 package into rectangles with silk screen printing further includes: drawing different identification symbols with silk screen according to different functions and uses of the electronic device.

In some embodiments, the engineering confirmation of the design board using the 0402 package includes: confirming that the package of the design board using the 0402 package meets the process production requirements.

In some embodiments, the printed circuit board design using the method of grabbing the center of the pin includes: when designing the PCB, for a 0402 type package suitable for a BGA with a pitch of 1.0mm, using the center of a pin of the 0402 package as a grab Take the point where the 0402 packaged device is placed on the center of the pins of the appropriate pins of the BGA package with a pitch of 1.0mm.

In some embodiments, the front side of the printed circuit board is a BGA package, the back side is a 0402 package, and the corresponding pins of the BGA package and the 0402 package are completely overlapped.

In some implementations, the BGA package and the 0402 package are combined to form a new through-hole device that implements different signal connections on the front and back.

Another aspect of the embodiments of the present invention also provides a printed circuit board packaging design system based on 0402 packaging, including:

processor;

A memory, the memory stores instructions executable by the processor, and the processor implements the above method when executing the instructions.

The present invention has the following beneficial technical effects: the printed circuit board packaging design method and system based on the 0402 package provided by the embodiment of the present invention fully overlaps the pins of the front BGA package and the back 0402 package of the PCB package without having to modify the set BGA The vias are rearranged; without increasing the PCB board frame, the PCB layout and wiring design area is expanded, making the layout of the entire board device more neat, beautiful and generous; all 0402 package type configurations of BGA chips are realized The circuit and power supply Bypass are placed on the back of the BGA nearby, which greatly improves the functionality and reliability of the entire board; PCB designers do not need to find ways to delete vias and save vias during layout and wiring, which greatly improves PCB design. design efficiency.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is the schematic flow chart of the embodiment of the printed circuit board package design method based on 0402 package provided by the present invention;

Fig. 2 is a schematic diagram of an embodiment in which the BGA package and the 0402 package in the prior art PCB package are combined on the same side;

FIG. 3 is a schematic diagram of an embodiment of a regular octagonal pad of the 0402 package provided by the present invention;

Fig. 4 is the schematic diagram of an embodiment of the 0402 package and the via hole on the back side of the PCB package provided by the present invention;

Fig. 5 is the schematic diagram of an embodiment of the front BGA package of PCB package provided by the present invention and via;

FIG. 6 is a schematic diagram of an embodiment in which the front BGA package and the back 0402 package and vias are combined on the same side provided by the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are to distinguish two entities with the same name but different parameters or parameters that are not the same, see "first" and "second" It is only for the convenience of expression, and should not be construed as a limitation on the embodiments of the present invention, which will not be described one by one in the subsequent embodiments.

Based on the above purpose, the first aspect of the embodiments of the present invention proposes an embodiment of a printed circuit board package design method based on 0402 package. FIG. 1 is a schematic flowchart of an embodiment of the method for designing a printed circuit board package based on an 0402 package provided by the present invention.

The printed circuit board package design method based on 0402 package, optionally, includes the following steps:

Step S101, designing the pads of the 0402 package into an octagonal shape;

Step S102, adaptively modify the center pin spacing of the two pads of the 0402 package;

Step S103, enclosing the two pads of the 0402 package into a rectangular shape with silk screen printing;

Step S104, carrying out engineering confirmation on the design board adopting 0402 package;

Step S105, adopting the method of grabbing the pin center to design the printed circuit board.

According to some embodiments, the PCB layout design and fabrication can use, for example, CADENCE ALLEGRO wiring design software and Pad designer PCB package design software.

FIG. 2 is a schematic diagram of an embodiment in which a BGA package and an 0402 package are combined on the same side in the prior art PCB package design.

As shown in Figure 2, the solid circles are the BGA pads with a pitch of 1.0MM, the small squares are the pads of the 0402 package, and the circles with dots are the via holes required for BGA wiring. It is known that the distance between the via hole and the pad (via to pin) is usually maintained at 8mil, and the minimum is 5mil. It can be seen from this figure that since the BGA needs via holes to lead out, the space for placing devices on the back of the BGA is very limited. Even if the 0402 package device is placed, the distance between the square pad and the via hole cannot meet the requirements of the PCB manufacturing process. Vias must be removed. However, there are very few vias that can be deleted. The BGA pins must be drilled to meet the requirements of the manufacturing process and complete the circuit connection.

FIG. 3 is a schematic diagram of an embodiment of a regular octagonal pad of a 0402 package provided by the present invention.

In a preferred embodiment, designing the pads of the 0402 package into an octagonal shape includes: using printed circuit board package design software to change the square pads of the 0402 package into a regular octagonal shape with an inscribed circle diameter d3=24mil. The modified pad increases the distance between the edge of the pad and the edge of the signal via, ensuring that the distance between the via and the pad is greater than 5mil. Theoretically, the number of 0402 type devices that can be placed on the back of the BGA is half of the BGA pins, which greatly expands the PCB layout space.

In a preferred embodiment, the adaptive modification of the central pin spacing of the two pads of the 0402 package includes: adapting the distance between the pins of two adjacent BGA pads to the center tube of the two pads of the 0402 package The pin spacing is set to a spacing value of d2 = 1.0mm (39.37mil). The center pin spacing of the 2 pads of the 0402 package is adapted to the spacing value between the pins of the BGA pads with a pitch of 1.0mm.

In a preferred embodiment, enclosing the two pads of the 0402 package with silkscreen into a rectangle includes: drawing the silkscreen on the 0402 package with a distance of 3 mils to the pads in the 0402 package. This distance can ensure that the actually produced PCB products can see clearly the pads and the silk screen.

In a preferred embodiment, enclosing the two solder pads of the 0402 package into a rectangular shape with silk screen further includes: drawing different identification symbols with silk screen according to different functions and uses of the electronic device. This allows for easier identification of electronic devices.

In a preferred embodiment, the engineering confirmation of the design board using the 0402 package includes: confirming that the package of the design board using the 0402 package meets the process production requirements. In some embodiments, the design board with the new 0402 package can be forwarded to the company's design for manufacturability (DFM) engineer and PCB board factory and printed circuit board assembly surface mount technology (PCBA SMT) patch factory for engineering Confirm, confirm that the package meets the process production requirements.

FIG. 4 is a schematic diagram of an embodiment of the 0402 package and via holes on the back side of the PCB package provided by the present invention. FIG. 5 is a schematic diagram of an embodiment of the front BGA package and via holes of the PCB package provided by the present invention. FIG. 6 is a schematic diagram of an embodiment in which the front BGA package and the back 0402 package and vias are combined on the same side provided by the present invention.

As shown in Figure 4, 401 represents the 0402 package, and the rectangular blocks similar to 401 in the figure are all 0402 packages; 402 represents vias, and the white dots similar to 402 in the figure are all vias; 403 represents the octagonal pads of the 0402 package , those similar to 403 in the figure are all 0402 package pads. As shown in Figure 5, 501 represents a via hole, and the white dots similar to 501 in the figure are via holes; 502 represents a BGA pad, and the gray dots similar to 502 in the figure are BGA pads. As shown in Figure 6, 601 represents the 0402 package, and the rectangular squares similar to 601 in the figure are all 0402 packages; 602 represents the via hole, and the white dots similar to 602 in the figure are all via holes; 603 represents the 0402 package pad, as shown in Figure 6. Those similar to 603 are 0402 package pads; 604 represents BGA pads, and the gray dots similar to 604 in the figure are BGA pads whether they coincide with 603 or not.

In a preferred embodiment, adopting the method of grasping the pin center to carry out the printed circuit board design includes: when carrying out PCB design, for the 0402 type package that is suitable for the BGA that the spacing is 1.0mm, take the center of a pin of the 0402 package as Grab the point and place the 0402 packaged device on the pin center of the appropriate pin on the 1.0mm pitch BGA package. The advantage of this operation is that the device is placed once and does not need to be moved. This placement method and packaging form already meet the requirements of the PCB process. If the vias are not deleted, the process will not be defective, and the remaining vias are used for more PCB wiring through layers.

In a preferred embodiment, the front side of the printed circuit board is a BGA package, and the back side is a 0402 package, and the corresponding pins of the BGA package and the 0402 package are completely overlapped. This can make the PCB package more neat, beautiful and elegant, and save the working time of the wiring design engineer.

In a preferred embodiment, the BGA package and the 0402 package are combined to form a new through-hole device that realizes different signal connections on the front and back.

There are two types of PCB boards: single-sided pendulum devices and double-sided pendulum devices. PCBs with BGA packages will be double-sided pendulum devices. The conventional practice is: put the BGA on the front of the PCB, and put its configuration resistance and capacitance on the back of the PCB. Just like writing on the front of a page, you can also write on the back, without interference. Vias interfere with devices placed on both sides.

The core technology of the invention is to completely overlap the front and back sides of the 1.0mm BGA pins after layout and the pins of the 0402 type package, so that there is no need to rearrange the set BGA via holes. It can be seen from Figure 6 that the combination of BGA and 0402 packages forms a new through-hole device, but the front and back of this new through-hole device can realize different signal connections, realizing some functions of the HDI board, while PCB design and manufacturing process costs will not increase.

It can be seen from the above embodiments that the printed circuit board package design method based on the 0402 package provided by the embodiment of the present invention completely overlaps the front and back of the 1.0mmBGA pin after layout and the pin of the 0402 type package, thereby eliminating the need to The set BGA vias are rearranged. This technology expands the PCB layout and wiring design area without increasing the PCB board frame, and at the same time makes the entire board device layout more neat, beautiful and generous. This technology can realize all 0402 package type configuration circuits of BGA chips, and the power bypass is placed on the back of BGA nearby, which greatly improves the functionality and reliability of the entire board. PCB designers no longer need to painstakingly move the device a little bit when laying out the wiring, racking their brains to figure out how to save a through hole, saving time and effort, and greatly improving the design efficiency of PCB design.

It should be pointed out that the steps in the above embodiments of the printed circuit board packaging design method based on 0402 packaging can be intersected, replaced, added, and deleted. Therefore, these reasonable permutations and combinations are different from those based on 0402 packaging. The printed circuit board packaging design method should also belong to the protection scope of the present invention, and the protection scope of the present invention should not be limited to the above embodiments.

The above are exemplary embodiments disclosed in the present invention, and the sequence disclosed in the above embodiments of the present invention is only for description, and does not represent the advantages or disadvantages of the embodiments. However, it should be noted that the discussion of any of the above embodiments is exemplary only, and is not intended to imply that the scope (including the claims) disclosed by the embodiments of the present invention is limited to these examples. Various changes and modifications are made. The functions, steps and/or actions of the method claims in accordance with the disclosed embodiments described herein need not be performed in any particular order. In addition, although the elements disclosed in the embodiments of the present invention may be described or required in an individual form, they may also be understood as a plurality unless explicitly limited to a singular number.

Based on the above purpose, in the second aspect of the embodiment of the present invention, a printed circuit board packaging design system based on 0402 packaging is proposed. The printed circuit board packaging design system based on 0402 packaging includes a processor and a memory, and the memory stores Instructions executable by the processor, when the processor executes the instructions, implements the 0402 package-based printed circuit board package design method described in the present invention.

The embodiment of the present invention provides a printed circuit board package design system based on 0402 package, so that the layout of the 1.0mmBGA pin and the pin front and back of the 0402 type package completely overlap, so that there is no need to re-set the BGA via hole. arranged. This technology expands the PCB layout and wiring design area without increasing the PCB board frame, and at the same time makes the entire board device layout more neat, beautiful and generous. This technology can realize all 0402 package type configuration circuits of BGA chips, and the power bypass is placed on the back of BGA nearby, which greatly improves the functionality and reliability of the entire board. PCB designers no longer need to painstakingly move the device a little bit when laying out the wiring, racking their brains to figure out how to save a through hole, saving time and effort, and greatly improving the design efficiency of PCB design.

It should be pointed out that the above embodiment of the printed circuit board package design system based on 0402 package uses the embodiment of the 0402 package printed circuit board package design method to specifically illustrate the working process of each module. Those skilled in the art can It is readily conceivable to apply these modules to other embodiments of the printed circuit board package design method for the 0402 package. Of course, since the various steps in the embodiment of the printed circuit board packaging design method of the 0402 package can be intersected, replaced, added, and deleted, these reasonable permutations and combinations are different from those of the printed circuit board packaged in the 0402 package. The package design system should also belong to the protection scope of the present invention, and the protection scope of the present invention should not be limited to the above embodiments.

Those of ordinary skill in the art should understand that: the discussion of any of the above embodiments is exemplary only, and is not intended to imply that the scope (including claims) disclosed by the embodiments of the present invention is limited to these examples; under the idea of the embodiments of the present invention , technical features in the above embodiments or in different embodiments can also be combined, and there are many other changes in different aspects of the embodiments of the present invention as described above, which are not provided in details for the sake of brevity. Therefore, within the spirit and principle of the embodiments of the present invention, any omissions, modifications, equivalent replacements, improvements, etc., shall be included in the protection scope of the embodiments of the present invention.

Claims (10)

1. a kind of printed circuit board based on 0402 encapsulation encapsulates design method, which is characterized in that include the following steps：

The pad design that described 0402 is encapsulated is octagonal shape；

The center lead pin pitch of 2 pads of 0402 encapsulation described in adaptation；

2 pads silk-screen circle rectangularity that described 0402 is encapsulated；

Engineering confirmation is carried out to the layout board card using 0402 encapsulation；

PCB design is carried out using the method at crawl pin center.

2. the method according to claim 1, wherein the pad design that described 0402 is encapsulated is octagonal shape Including：It is 24mil that the square pads that described 0402 encapsulates, which are changed to inscribed circle diameter, using printed circuit board encapsulation design software Polygon-octagonal shape.

3. the method according to claim 1, wherein in 2 pads of 0402 encapsulation described in adaptation Heart lead pin pitch includes：It is adapted to 2 pads that the distance between the pins of 2 neighbouring BGA pads is encapsulated described 0402 It is 1.0mm that center lead pin pitch, which is set as distance values,.

4. the method according to claim 1, wherein 2 pads silk-screen circle that described 0402 is encapsulated Rectangularity includes：0402 encapsulation is drawn to the silk-screen for being 3mil to the distance of the pad in 0402 encapsulation.

5. according to the method described in claim 4, it is characterized in that, 2 pads silk-screen circle that described 0402 is encapsulated Rectangularity further comprises：According to the different function and purposes of electronic device, different identifiers is drawn with silk-screen.

6. the method according to claim 1, wherein carrying out engineering to the layout board card using 0402 encapsulation Confirmation includes：Technique production requirement will be met using the design board confirmation encapsulation of 0402 encapsulation.

7. the method according to claim 1, wherein carrying out printed circuit board using the method at crawl pin center Design includes：When carrying out PCB design, for being adapted to 0402 type package for the BGA that spacing is 1.0mm, with described One pin center of 0402 encapsulation is crawl point, and 0402 packaging is placed on the suitable of the BGA package that spacing is 1.0mm On the pin center of pin.

8. the method according to the description of claim 7 is characterized in that the front of the printed circuit board is the BGA package, back Face is 0402 encapsulation, and the BGA package and the respective pin of 0402 encapsulation are completely overlapped.

9. method according to claim 7 or 8, which is characterized in that the BGA package and the 0402 encapsulation combination are one It rises and forms the new via hole device that different signal connections is realized at a positive back side.

10. a kind of printed circuit board package design system based on 0402 encapsulation, which is characterized in that including：

Processor；

Memory, the memory are stored with the executable instruction of the processor, and the processor is when executing described instruction Realize method described in any one of claim 1-9.