Today’s electronic products are ubiquitous, and the PCB circuit boards utilized in various devices come in different colors, shapes, sizes, and materials tailored to specific industries. Therefore, understanding the intricacies involved in PCB circuit board design is essential, as misunderstandings can easily arise.
1. The definition of processing levels can often be ambiguous: a single-sided board is designed on the TOP layer. If the distinctions between the positive and negative sides are not clearly defined, soldering components onto the board may prove challenging.
2. The distance between the large copper areas and the outer frame is insufficient: There should be a minimum distance of 0.2mm between the large copper areas and the outer frame. This is important because, during the milling process, proximity can cause the copper to warp, leading to issues such as flux drop.
3. Drawing pads with filler blocks: While pads with filler blocks can be checked using DRC during PCB design, the processing is often inadequate. Consequently, similar pads cannot directly generate solder mask data. When applying solder resist, the area of the filler block will be covered, complicating the soldering of components.
4. The electrical ground layer functions as both a flower pad and a connection: Since it is designed as a flower pad for power supply, the ground layer will appear reversed on the actual printed board. All connections must be isolated. Multiple power supply or ground groups should be carefully isolated to avoid gaps that could short-circuit and block connection areas.
5. Characters are haphazardly placed: The SMD soldering pads for the character cover pads hinder the on-off testing of the PCB and the soldering of components. If character designs are too small, they may not print clearly, while overly large designs can lead to overlapping characters, making them hard to read.
6. Surface mount device pad length is inadequate: This is particularly relevant for continuity testing. For densely packed surface mount devices, the space between pins is minimal, and pads are often thin. Test probes must be positioned in an interlaced manner. If the pad is too short, it won’t affect the device’s functionality but will make it difficult for test pins to be staggered.
7. Setting pad aperture for single-sided pads: Typically, single-sided pads are not drilled. If drilling is necessary, the aperture should be set to zero. Designing it with a numerical value can lead to issues during drilling data generation, as it may show hole coordinates in the wrong location. Special markings should indicate when drilling is needed on single-sided pads.
8. Pad stacking concerns: The drilling process on a PCB can lead to drill bit breakage due to repeated drilling in the same area, causing hole damage. In multi-layer boards, stacked holes can create problems, and the negative film may need to be drawn as an isolation disk, resulting in scrap.
1. The definition of processing levels can often be ambiguous: a single-sided board is designed on the TOP layer. If the distinctions between the positive and negative sides are not clearly defined, soldering components onto the board may prove challenging.
2. The distance between the large copper areas and the outer frame is insufficient: There should be a minimum distance of 0.2mm between the large copper areas and the outer frame. This is important because, during the milling process, proximity can cause the copper to warp, leading to issues such as flux drop.
3. Drawing pads with filler blocks: While pads with filler blocks can be checked using DRC during PCB design, the processing is often inadequate. Consequently, similar pads cannot directly generate solder mask data. When applying solder resist, the area of the filler block will be covered, complicating the soldering of components.
4. The electrical ground layer functions as both a flower pad and a connection: Since it is designed as a flower pad for power supply, the ground layer will appear reversed on the actual printed board. All connections must be isolated. Multiple power supply or ground groups should be carefully isolated to avoid gaps that could short-circuit and block connection areas.
5. Characters are haphazardly placed: The SMD soldering pads for the character cover pads hinder the on-off testing of the PCB and the soldering of components. If character designs are too small, they may not print clearly, while overly large designs can lead to overlapping characters, making them hard to read.
6. Surface mount device pad length is inadequate: This is particularly relevant for continuity testing. For densely packed surface mount devices, the space between pins is minimal, and pads are often thin. Test probes must be positioned in an interlaced manner. If the pad is too short, it won’t affect the device’s functionality but will make it difficult for test pins to be staggered.
7. Setting pad aperture for single-sided pads: Typically, single-sided pads are not drilled. If drilling is necessary, the aperture should be set to zero. Designing it with a numerical value can lead to issues during drilling data generation, as it may show hole coordinates in the wrong location. Special markings should indicate when drilling is needed on single-sided pads.
8. Pad stacking concerns: The drilling process on a PCB can lead to drill bit breakage due to repeated drilling in the same area, causing hole damage. In multi-layer boards, stacked holes can create problems, and the negative film may need to be drawn as an isolation disk, resulting in scrap.
