[Repost] 7 PCB layout principles, good PCB design depends on it

皇华Ameya360

[Repost] 7 PCB layout principles, good PCB design depends on it [Copy link]

(1) It is best to place components on one side. If you need to place components on both sides, place pin-type components on the bottom layer (BottomLayer). It is best to place components on one side. This may make the circuit board difficult to place and not conducive to soldering. Therefore, it is best to place only SMD components on the bottom layer (BottomLayer), similar to the common component arrangement method on computer graphics card PCB boards. When placing components on one side, only one side of the circuit board needs to be printed with a silk screen layer to reduce costs. (2) Reasonably arrange the position and direction of interface components. Generally speaking, connector components that connect the circuit board to the outside world (power supply, signal line) are usually arranged at the edge of the circuit board, such as serial port and parallel port. If placed in the center of the circuit board, it is obviously not conducive to wiring. Connector components may also be unable to connect due to obstruction of other components. In addition, pay attention to the direction of the interface when placing the interface so that the connecting line can be smoothly led out and away from the circuit board.

After the interface is placed, the type of interface should be clearly marked with the string of the interface component; for power interfaces, the voltage level should be marked to prevent the circuit board from burning due to wiring errors.

(3) It is best to have a wider electrical isolation zone between high-voltage components and low-voltage components.

That is to say, do not place components with very different voltage levels together. It is best to have a wider electrical isolation zone between high-voltage components and low-voltage components. Do not place components with very different voltage levels together. This is not only conducive to electrical insulation, but also has great benefits for signal isolation and anti-interference.

[color=rgb(25, 25, (25)]（4）Components with close electrical connections are best placed together. This is the idea of modular layout.

（5）For components that are prone to noise, such as high-frequency devices such as clock generators and crystal oscillators, they should be placed at the clock input end as much as possible.

High current circuits and switching circuits are also prone to noise. When laying out, these components or modules should also be kept away from high-speed signal circuits such as logic control circuits and storage circuits. If possible, try to use the control board combined with the power board and use the interface to connect to improve the overall anti-interference ability and working reliability of the circuit board.

（6）Place decoupling capacitors and filter capacitors around the power supply and chip as much as possible. The arrangement of decoupling capacitors and filter capacitors is an important measure to improve the power quality of circuit boards and enhance anti-interference capabilities. In practical applications, the routing, pin connections and wiring of printed circuit boards may bring about large parasitic inductance, resulting in high-frequency ripples and glitches in the power waveform and signal waveform. Placing between the power supply and the ground may bring about large parasitic inductance, resulting in high-frequency ripples and glitches in the power waveform and signal waveform. A 0.1F decoupling capacitor can effectively filter out these high-frequency ripples and glitches. If chip capacitors are used on the circuit board, the chip capacitors should be placed close to the power pins of the components. For the power conversion chip or the power input terminal, it is best to arrange a 10F or larger capacitor to further improve the power quality. (7) The numbers of components should be arranged close to the borders of the components, with uniform size and neat direction, and should not overlap with components, vias and pads. The first pin of the component or connector indicates the direction; the positive and negative poles should be clearly marked on the PCB and are not allowed to be covered; there should be enough heat dissipation space and installation space next to the power conversion components (such as DC/DC converters, linear conversion power supplies and switching power supplies), and enough welding space should be left on the periphery. Source: Internet, if infringed, please delete.

烟落无痕

That makes sense!