Before diving into the PCB circuit board design process, it’s essential to first understand what a PCB is. PCB stands for Printed Circuit Board, which refers to conductive patterns made from printed circuits, printed components, or a combination of both, arranged on insulating materials based on a specific design. These are generally referred to as printed circuits.
The PCB technology originated in 1936, and by 1943, it was widely used in military radios in the United States. Since the mid-1950s, PCB technology has seen widespread adoption. Today, PCBs are considered the “mother of electronic products,” with applications extending to nearly all sectors of the electronics industry, such as computers, telecommunications, consumer electronics, industrial automation, medical devices, defense, military, aerospace, and more. The following is a comprehensive overview of the PCB design process, compiled by the Fast PCB Academy.
1. **Preliminary Preparation**
This step includes the creation of component libraries and schematic diagrams. Before starting the PCB design, it’s crucial to first prepare the schematic (SCH) component library and the PCB component packaging library.
1. **PCB Component Package Library**
The PCB component package library should ideally be established by the engineer based on the standard size data of the selected components. In principle, the component package library should be created first, followed by the creation of the schematic (SCH) component library.
The PCB component package library has stringent requirements as it directly affects the PCB installation. In contrast, the schematic (SCH) component library has relatively looser requirements, but attention should be paid to defining the pin attributes and ensuring the correct mapping to the PCB component package library.
2. **PCB Structure Design**
Based on the determined circuit board size and mechanical positioning, draw the PCB frame in the PCB design environment. Place the necessary components, such as connectors, buttons/switches, screw holes, and assembly holes, according to the positioning specifications.
It is essential to thoroughly consider and define the wiring and non-wiring areas (for instance, determining how much area around the screw holes is non-wiring space).
3. **PCB Layout Design**
PCB layout design involves placing components within the PCB frame according to the design specifications. First, generate the netlist (Design → Create Netlist) in the schematic tool, and then import the netlist (Design → Import Netlist) into the PCB software. After a successful import, the netlist will exist in the software’s background. Through the placement operation, all components can be brought into view, with fly-line prompts indicating the pin-to-pin connections. At this point, the component layout design can proceed.
The layout design is a critical stage in the PCB design process. The more complex the PCB, the more significant the impact of a good layout on the difficulty of routing later on.
Layout design requires a solid foundation in circuit knowledge and significant design experience, making it a high-level skill. Junior PCB designers with limited experience are more suited to smaller modules or less complex PCB layout tasks.
4. **PCB Routing Design**
PCB routing design is the most labor-intensive phase in the entire PCB design process and has a direct impact on the board’s performance.
In PCB design, routing generally falls into three stages:
– The first stage is distribution, which serves as the most basic entry-level requirement for PCB design.
– The second stage focuses on meeting electrical performance standards, which are critical to determining whether the PCB is functional. After routing is completed, it is essential to adjust the routing to optimize electrical performance.
– The third stage is about neatness and aesthetics. Even if the electrical performance is satisfactory, disorganized routing can cause significant difficulties during later modifications, optimizations, testing, and maintenance. Routing should be clean, orderly, and avoid crossing lines or chaotic patterns.
5. **Routing Optimization and Silk Screen Placement**
“PCB design is never perfect, only better,” and “PCB design is an art of compromise.” This is because PCB design must balance various hardware requirements, and these requirements often conflict with each other. As the saying goes, “You can’t have it all.”
For example, after evaluating a PCB design, a circuit designer might decide on a 6-layer board, but due to cost constraints, the hardware is ultimately designed as a 4-layer board. This might necessitate sacrificing the signal shielding ground layer, which leads to increased signal crosstalk between adjacent layers and a decrease in signal quality.
A general rule of thumb is that the time required for routing optimization is typically twice the time spent on the initial routing. Once PCB layout optimization is complete, post-processing is needed, including the placement of silk screen labels on the PCB surface. The bottom layer’s silk screen text should be mirrored during the design to avoid confusion with the top layer.
6. **Netlist DRC Check and Structural Inspection**
Quality control is a critical aspect of the PCB design process. Common quality control methods include design self-checks, peer reviews, expert review sessions, and specialized inspections.
The schematic and structural element diagrams form the fundamental requirements of the design. Network DRC checks and structural inspections are used to verify that the PCB design adheres to the schematic netlist and structural requirements.
Circuit board designers typically maintain their own design quality checklists, which are partly based on company or departmental standards and partly on the designer’s personal experience. Special inspections may include Valor and DFM checks, focusing on the design’s integrity and its output Gerber files for manufacturing.
7. **PCB System Board**
Before the PCB enters formal processing and production, the circuit board designer must communicate with the PCB supplier’s process engineer (PE) to address any manufacturing-related queries.
This communication covers, but is not limited to, the selection of PCB materials, adjustments to circuit layer trace widths and spacings, impedance control, PCB stack-up thickness, surface treatment processes, hole diameter tolerances, and delivery specifications.
If you have any PCB manufacturing needs, please do not hesitate to contact me.Contact me
The PCB technology originated in 1936, and by 1943, it was widely used in military radios in the United States. Since the mid-1950s, PCB technology has seen widespread adoption. Today, PCBs are considered the “mother of electronic products,” with applications extending to nearly all sectors of the electronics industry, such as computers, telecommunications, consumer electronics, industrial automation, medical devices, defense, military, aerospace, and more. The following is a comprehensive overview of the PCB design process, compiled by the Fast PCB Academy.
1. **Preliminary Preparation**
This step includes the creation of component libraries and schematic diagrams. Before starting the PCB design, it’s crucial to first prepare the schematic (SCH) component library and the PCB component packaging library.
1. **PCB Component Package Library**
The PCB component package library should ideally be established by the engineer based on the standard size data of the selected components. In principle, the component package library should be created first, followed by the creation of the schematic (SCH) component library.
The PCB component package library has stringent requirements as it directly affects the PCB installation. In contrast, the schematic (SCH) component library has relatively looser requirements, but attention should be paid to defining the pin attributes and ensuring the correct mapping to the PCB component package library.
2. **PCB Structure Design**
Based on the determined circuit board size and mechanical positioning, draw the PCB frame in the PCB design environment. Place the necessary components, such as connectors, buttons/switches, screw holes, and assembly holes, according to the positioning specifications.
It is essential to thoroughly consider and define the wiring and non-wiring areas (for instance, determining how much area around the screw holes is non-wiring space).
3. **PCB Layout Design**
PCB layout design involves placing components within the PCB frame according to the design specifications. First, generate the netlist (Design → Create Netlist) in the schematic tool, and then import the netlist (Design → Import Netlist) into the PCB software. After a successful import, the netlist will exist in the software’s background. Through the placement operation, all components can be brought into view, with fly-line prompts indicating the pin-to-pin connections. At this point, the component layout design can proceed.
The layout design is a critical stage in the PCB design process. The more complex the PCB, the more significant the impact of a good layout on the difficulty of routing later on.
Layout design requires a solid foundation in circuit knowledge and significant design experience, making it a high-level skill. Junior PCB designers with limited experience are more suited to smaller modules or less complex PCB layout tasks.
4. **PCB Routing Design**
PCB routing design is the most labor-intensive phase in the entire PCB design process and has a direct impact on the board’s performance.
In PCB design, routing generally falls into three stages:
– The first stage is distribution, which serves as the most basic entry-level requirement for PCB design.
– The second stage focuses on meeting electrical performance standards, which are critical to determining whether the PCB is functional. After routing is completed, it is essential to adjust the routing to optimize electrical performance.
– The third stage is about neatness and aesthetics. Even if the electrical performance is satisfactory, disorganized routing can cause significant difficulties during later modifications, optimizations, testing, and maintenance. Routing should be clean, orderly, and avoid crossing lines or chaotic patterns.
5. **Routing Optimization and Silk Screen Placement**
“PCB design is never perfect, only better,” and “PCB design is an art of compromise.” This is because PCB design must balance various hardware requirements, and these requirements often conflict with each other. As the saying goes, “You can’t have it all.”
For example, after evaluating a PCB design, a circuit designer might decide on a 6-layer board, but due to cost constraints, the hardware is ultimately designed as a 4-layer board. This might necessitate sacrificing the signal shielding ground layer, which leads to increased signal crosstalk between adjacent layers and a decrease in signal quality.
A general rule of thumb is that the time required for routing optimization is typically twice the time spent on the initial routing. Once PCB layout optimization is complete, post-processing is needed, including the placement of silk screen labels on the PCB surface. The bottom layer’s silk screen text should be mirrored during the design to avoid confusion with the top layer.
6. **Netlist DRC Check and Structural Inspection**
Quality control is a critical aspect of the PCB design process. Common quality control methods include design self-checks, peer reviews, expert review sessions, and specialized inspections.
The schematic and structural element diagrams form the fundamental requirements of the design. Network DRC checks and structural inspections are used to verify that the PCB design adheres to the schematic netlist and structural requirements.
Circuit board designers typically maintain their own design quality checklists, which are partly based on company or departmental standards and partly on the designer’s personal experience. Special inspections may include Valor and DFM checks, focusing on the design’s integrity and its output Gerber files for manufacturing.
7. **PCB System Board**
Before the PCB enters formal processing and production, the circuit board designer must communicate with the PCB supplier’s process engineer (PE) to address any manufacturing-related queries.
This communication covers, but is not limited to, the selection of PCB materials, adjustments to circuit layer trace widths and spacings, impedance control, PCB stack-up thickness, surface treatment processes, hole diameter tolerances, and delivery specifications.
If you have any PCB manufacturing needs, please do not hesitate to contact me.Contact me
