1: The composition of relevant design elements in the PCB should be clearly defined within the design specification. The shape is represented by mechanical layers 1 to 16 (in order of priority) or a no-entry layer. When both are used in the PCB design file, a common shielding layer can be employed to disable routing, rather than opening holes. The machine layer 1 should be used for molding. In the PCB design drawing, a long slot or cutout should be shown, with the corresponding shape drawn on the “mechanical 1” layer.
2: Overall Dimension Tolerance
The size of the PCB must adhere to the design specifications. If no specific dimensions are provided, the dimensional tolerance should be ±0.2mm.
3: Flatness (Warpage) 0.7%
What is the concept of stratification?
1: For a single-layer board, the signal layer is drawn on the top layer, indicating that the traces on this layer represent the outer surface.
2: Draw a signal layer on the bottom layer of the single-sided PCB, indicating that the traces on this layer will be on the surface.
3: For a double-sided PCB, I assume the top layer is the component side (top layer), where the silkscreen text is placed. The bottom layer (bottom layer) is the solder side, and the silkscreen text on the bottom layer will appear inverted.
4: Multi-layer stack-up instructions should be provided to the Layer Stack Manager for Protel99SE version. For Protel98, include the logo or software sequence, and for layer instructions, specify the pads series design software.
**Printed Traces and Pads**
1: **PCB Layout**
The layout, trace width, and spacing of printed conductors and pads are primarily determined by the design requirements. However, I follow these guidelines: based on the process specifications, I compensate for trace width and pad ring width. To enhance soldering reliability, we typically increase the pad size on single-sided boards. If the designed trace spacing does not meet process standards (too dense, which could affect performance and manufacturability), we make necessary adjustments according to design specifications before production.
In general, it’s recommended that customers design double-sided or multi-layer boards. For through-holes (VIA), the inner diameter should be 0.3mm or larger, and the outer diameter should be 0.6mm or larger. The component pad should be 50% larger than the hole diameter. For small-sized boards, a thickness of 6 mil is ideal.
1: For tin-plating, the trace width and spacing should be designed to be no less than 6 mil. For gold-plating processes, traces should be designed to be no less than 4 mil to help shorten production time and ease manufacturing challenges.
2: **Trace Width Tolerance**: The tolerance for trace width should be controlled within 20% according to internal standards.
3: **Grid Processing**: To avoid blistering and thermal stress on the copper surface when the PCB is bent during peak printing, it’s recommended to use a grid pattern for large copper areas. The grid spacing should be no less than 10 mil (ideally 8 mil), and the grid line width should be no less than 8 mil.
4: **Heat Shield (Thermal Insulation Pad)**: For large-area ground planes or areas with frequent component leads, the pads connecting the component leads should be designed with electrical and process considerations in mind. Cross-hatch pads (insulation pads) are ideal as they reduce the risk of poor soldering due to excessive cooling in the section.
5: **Inner Traces & Copper Isolation**: For drill holes with an isolation area of 0.3mm, it’s recommended to insulate the ground pins of PCB components. The distance between the copper foil and the edge of the board should be at least 0.3mm, and external traces, the edges of copper areas, and gold finger positions should be free from copper to avoid the risk of short circuits caused by exposed copper.
If you have any PCB manufacturing needs, please do not hesitate to contact me.Contact me
2: Overall Dimension Tolerance
The size of the PCB must adhere to the design specifications. If no specific dimensions are provided, the dimensional tolerance should be ±0.2mm.
3: Flatness (Warpage) 0.7%
What is the concept of stratification?
1: For a single-layer board, the signal layer is drawn on the top layer, indicating that the traces on this layer represent the outer surface.
2: Draw a signal layer on the bottom layer of the single-sided PCB, indicating that the traces on this layer will be on the surface.
3: For a double-sided PCB, I assume the top layer is the component side (top layer), where the silkscreen text is placed. The bottom layer (bottom layer) is the solder side, and the silkscreen text on the bottom layer will appear inverted.
4: Multi-layer stack-up instructions should be provided to the Layer Stack Manager for Protel99SE version. For Protel98, include the logo or software sequence, and for layer instructions, specify the pads series design software.
**Printed Traces and Pads**
1: **PCB Layout**
The layout, trace width, and spacing of printed conductors and pads are primarily determined by the design requirements. However, I follow these guidelines: based on the process specifications, I compensate for trace width and pad ring width. To enhance soldering reliability, we typically increase the pad size on single-sided boards. If the designed trace spacing does not meet process standards (too dense, which could affect performance and manufacturability), we make necessary adjustments according to design specifications before production.
In general, it’s recommended that customers design double-sided or multi-layer boards. For through-holes (VIA), the inner diameter should be 0.3mm or larger, and the outer diameter should be 0.6mm or larger. The component pad should be 50% larger than the hole diameter. For small-sized boards, a thickness of 6 mil is ideal.
1: For tin-plating, the trace width and spacing should be designed to be no less than 6 mil. For gold-plating processes, traces should be designed to be no less than 4 mil to help shorten production time and ease manufacturing challenges.
2: **Trace Width Tolerance**: The tolerance for trace width should be controlled within 20% according to internal standards.
3: **Grid Processing**: To avoid blistering and thermal stress on the copper surface when the PCB is bent during peak printing, it’s recommended to use a grid pattern for large copper areas. The grid spacing should be no less than 10 mil (ideally 8 mil), and the grid line width should be no less than 8 mil.
4: **Heat Shield (Thermal Insulation Pad)**: For large-area ground planes or areas with frequent component leads, the pads connecting the component leads should be designed with electrical and process considerations in mind. Cross-hatch pads (insulation pads) are ideal as they reduce the risk of poor soldering due to excessive cooling in the section.
5: **Inner Traces & Copper Isolation**: For drill holes with an isolation area of 0.3mm, it’s recommended to insulate the ground pins of PCB components. The distance between the copper foil and the edge of the board should be at least 0.3mm, and external traces, the edges of copper areas, and gold finger positions should be free from copper to avoid the risk of short circuits caused by exposed copper.
If you have any PCB manufacturing needs, please do not hesitate to contact me.Contact me
