The golden principle of PCB design will never change

Despite the increasing integration of semiconductors, many applications also have ready-to-use on-chip systems. At the same time, many powerful and out-of-the-box development boards are increasingly accessible, however, in many use cases, the application of electronic products still needs to use custom PCB. In one-time development, even a general PCB can play a very important role. PCB is a physical platform for design and the most flexible component used for electronic system design of original components. This article will introduce several golden principles of PCB design, which have not changed since the birth of Commercial PCB design 25 years ago and are widely applied to various PCB design projects, both young electronic design engineers and more mature circuit board manufacturers have a great guiding role.

The following describes the ten most effective design rules that electronic design engineers should keep in mind and practice when using design software for PCB layout design and commercial manufacturing. Engineers do not need to execute these rules in sequence by time or relative importance, but simply follow them to greatly change the product design.
Rule 1: select the correct grid-set and always use the grid spacing that matches the most components.
Although the multi-grid seems to have a significant effect, if engineers can think more at the early stage of the PCB layout design, they will be able to avoid difficulties in the interval setting and maximize the application of the circuit board. Since many devices use a variety of packaging sizes, engineers should use products that are best suited to their own design. In addition, polygon is crucial for copper applying to the circuit board. Polygon padding deviation is generally generated when the polygon is applied to the multi-grid circuit board. Although it is not as standard as based on a single grid, however, the service life of the circuit board exceeds the required limits.
Rule 2: Keep the path shortest and direct.
This sounds simple, but it should be kept in mind at every stage, even if it means to change the layout of the board to optimize the wiring length. This is especially suitable for analog and high-speed digital circuits whose system performance is always limited by impedance and Parasitic effects.
Rule 3: Use the power supply layer to manage the distribution of power cords and ground wires.
Copper Coating on the power supply layer is a fast and simple option for most PCB design software. By using a large number of wires for shared connections, you can ensure the highest efficiency and the lowest impedance or pressure drop of the current, while providing adequate grounding backflow path. If possible, multiple power supply lines can be run in the same area of the circuit board to check whether the formation covers most layers of a certain layer of the PCB. This facilitates the interaction between lines on the adjacent layer.
Rule 4: group related components with the required test points.
For example, you can place the discrete components required by the opamp op amp in a location closer to the device so that the bypass capacitor and resistor can work with the same location to help optimize the wiring length mentioned in rule 2, it also makes testing and Fault Detection easier.
Rule 5: duplicate the required circuit board on another larger circuit board for multiple PCB imposition.
Selecting the size that best fits the device used by the manufacturer helps reduce prototyping and manufacturing costs. First, layout the circuit board on the panel, contact the circuit board manufacturer to obtain their preferred size and specifications for each panel, and then modify your design specifications, and try to repeat your design multiple times in these Panel sizes.

 

Rule 6: integrate component values.
As a designer, you will choose some discrete components with the same value or high or low performance. By integrating within a small range of standard values, you can simplify the bill of materials and reduce costs. If you have a series of PCB products based on the preferred device value, you will be able to make correct inventory management decisions in the long run.
Rule 7: perform as many design rule checks as possible (DRC ).
Although it takes only a short time to run the DRC function on PCB software, in a more complex design environment, you can save a lot of time by performing a check during the design process, this is a good habit worth keeping. Each cabling decision is critical. By executing DRC, you can always remind you of the most important cabling.
Rule 8: flexible use of screen printing.
Screen Printing can be used to mark various useful information for future use by circuit board makers, service or test engineers, installers, or equipment commissioning personnel. Not only are clear function and test point labels marked, but the orientation of components and connectors should be indicated as much as possible, even if the comments are printed on the lower surface of the component used by the circuit board (after assembly of the circuit board ). Full application of Screen Printing Technology on the upper and lower surfaces of the circuit board can reduce repetitive work and streamline the production process.
Rule 9: Required decoupling capacitor.
Do not try to optimize your design by avoiding decoupling the power cord and optimizing your design based on the limit value in the component data table. Capacitors are inexpensive and durable. You can spend as much time assembling the capacitors as possible, and follow Rule 6 to use the standard value range to keep the stock neat.
Rule 10: Generate PCB Manufacturing parameters and verify the parameters before submission to production.
Although most board manufacturers are happy to download and verify the file directly, you 'd better output the gerber file first and use the free generator to check whether the file is the same as expected to avoid misunderstanding. You may even find some neglected errors by yourself, so you can avoid losses caused by incorrect parameters.
As circuit design is sharing more and more widely, and internal teams rely more and more on reference design, the basic rules similar to the above will still be a feature of printed circuit board design, we believe this is very important for PCB design. With these basic rules clearly defined, developers can flexibly increase the value of their products and maximize the benefits of their manufactured circuit boards. Even a beginner in circuit board design, keeping these basic rules in mind can speed up the learning process and enhance confidence.