Despite the current semiconductor integration is higher and higher, many applications have also readily available on a chip system, at the same time many powerful and out-of-the-box development board is becoming more and more easily available, but many use cases still need to use custom PCB electronics applications. Among developed once, even a common PCB can play a very important role. PCB is the physical platform for design, is also used for the original component for electronic system design of the flexible components. This article introduces several kinds of PCB design golden rules, these rules since commercial PCB design is born 25 years ago, most do not have any change, and is widely used in all kinds of PCB design projects, both for young electronic design engineers and more mature circuit board manufacturers, has a great guiding role. This article introduced how to use electronic design engineers in the following design software for PCB layout design and commercial manufacturing should be kept in mind and practice of ten of the most effective design rule. Engineers need not in or relative importance, in turn, carry out these rules, just follow all can dramatically change the product design. Rule 1: choose the correct grid - set and always use to match the most components of the grid spacing. Although seemingly significant utility multiple grid, but if the engineer at the beginning of the PCB layout design thinking more, can avoid interval encountered problems and can maximize the application of circuit board. Because many families use a variety of package sizes, the engineer shall use the most conducive to their own design products. In addition, the polygon is vital for circuit board coated copper, multiple grid circuit boards in the polygon apply copper generally produces the polygon-filling deviation, though as well as based on a single grid standards, but it can offer beyond the service life of the circuit board. Rule 2: keep the path the shortest most direct. It sounds simple, but should be in each stage, even though it means want to change the PCB layout to optimize the wiring length, should be always remember. This part also is especially suitable for the system performance is always limited by impedance and simulation of the parasitic effect and high speed digital circuits. Rule 3: as far as possible, use the power the power cord and the distribution of the ground layer management. Power coated copper layer is faster for most of the PCB design software also relatively simple a matter of choice. Through a large number of wires to Shared connection, can guarantee to provide maximum efficiency and minimum impedance or voltage drop of current, at the same time provide sufficient ground return path. Possible, still can run multiple power supply in the area of the circuit board in the same line, confirm whether the ground layer covers most of the PCB a layer level, which facilitates the interaction between adjacent layer running on line. Rule 4: the related components and the required test points are grouped together. For example: place the discrete component needed for the OpAmp operational amplifier in closer from the device so that the bypass capacitor and resistor can collaborate with him, so as to help optimize rule 2 mentioned wiring length, at the same time also make test and fault detection becomes easier. Rule 5: the required PCB in another larger circuit boards PCB puzzle duplicated many times. Choose the most suitable manufacturers used equipment is beneficial to reduce the size of the prototype design and the manufacturing cost. On the front panel PCB layout in the first place, contact circuit board manufacturers to get their first choice for each panel size, then change your design specifications, within those panel size and try to repeat in your design. Rule 6: integration of component values. As a designer, you can choose some component values or high or low, but the efficiency of discrete component. Through integrating in smaller standard scope, can simplify the bom, and may reduce the cost. If you have a series of PCB products, based on the preferred device value from a long-term perspective, also in favor of the inventory management of the you make the right decisions. Rule 7: as much as possible to perform design rule check (DRC). In spite of the PCB software running on the DRC function takes a short time, but in a more complex design environment, as long as you always perform inspection in the process of design can save a lot of time, this is a worth keeping good habits. Each wiring is crucial decision, by performing a DRC may at any time to alert you that the most important wiring. Rule 8: flexible use silk screen printing. Silk screen printing can be used to indicate a variety of useful information, so that circuit board manufacturers, service, or test engineer, installation personnel or equipment debugging personnel to use in the future. Not only marks a clear function and test point label, as labeled components and the direction of the connector, even these comments printed circuit board in the use of components under the surface (after PCB assembly). Up and down in the circuit board surface fully application of screen printing technology can reduce repeated work and streamline the production process. Rule 9: will choose decoupling capacitor. Don't attempt to avoid decoupled power according to component data in the table limit value to optimize your design. Capacitor is cheap and durable, you can spend time as much as possible to good capacitor assembly, follow the law of six at the same time, the use of standard value range to maintain inventory and tidy. Rule 10: PCB manufacturing parameters and verify before submit the production. Although most of the circuit board manufacturers would be happy to direct download and verify for you, but you'd better first output Gerber files, and free viewer check as well as expected, in order to avoid misunderstanding. Through verification in person, you will find that even some careless mistakes, and thus avoid losses according to the error parameters of complete production. Because sharing circuit design is more and more widely, and internal team more and more rely on the reference design, similar to the above basic rule will remain a feature of the printed circuit board design, we believe it is very important for the PCB design. Clear the basic rules, developers can be very flexible to enhance the value of their products and get maximum benefits from the manufacture of PCB. Even the novice circuit board design, just keep in mind these basic rules will speed up the learning process, to enhance confidence.
