General principles of PCB Board component Layout *

General principles of PCB Board component layout:
The general principles that designers need to follow in the layout of PCB boards are as follows.
(1) Components preferably single-sided placement. If you need to place components on both sides, placing pin components on the bottom layer (Bottom layer), it is best to place the components one-sided. It is possible to cause the circuit board is not easy to place, also not conducive to welding, so in the bottom layer (Bottom layer) is best placed on the bottom (at the bottom) pieces, similar to the common computer graphics card PCB Layout method of the component. Single-sided placement only on one side of the circuit board to make a screen printing layer, easy to reduce costs.
(2) Reasonable arrangement of the location and direction of the interface components. In general, as a circuit board and the outside (power, signal line) connected to the general, as a circuit board and the outside (power, signal line) Generally speaking connector components, usually arranged on the edge of the circuit board, such as the serial port and the same port. If placed in the center of the circuit board, obviously not conducive to wiring, connector components, usually arranged on the edge of the circuit board, such as the serial port and the same port.
It is also possible to be unable to connect due to the obstruction of other components. In addition, when placing the interface to pay attention to the direction of the interface, so that the connection line can be placed in addition to the interface to pay attention to the direction of the interface, in addition to the interface should pay attention to the direction of the interface smoothly, away from the circuit board. Smooth out, away from the circuit board. After the interface is placed, the interface components should be clearly identified by the string (string) and the voltage rating should be indicated for the Power class interface to prevent the circuit board from burning due to wiring errors. For power class interfaces, the voltage level should be indicated to prevent the circuit board from burning due to wiring errors. For power class interfaces
(3) High-voltage components and low-voltage components should preferably have a wider electrical isolation belt. That is, do not vary the voltage level is very large) high-voltage components and low-voltage components preferably between a wider electrical isolation belt. Do not put a large voltage level of the components placed together, the components placed together, which is conducive to electrical insulation, signal isolation and anti-interference also has great benefits.
Bureau of thought. (4) Components with close connections to the electrical connection are best placed together. This is the idea of modular layout. Components with close connections to the electrical connection are best placed together. This is the modular layout idea.
(5) for noise-prone components, such as clock generators and crystal oscillator, such as high-frequency devices, when placed should be as far as possible to the noise-prone components, such as clock generators and crystal oscillator, such as high-frequency devices, the clock input. High-current circuits and switching circuits are also prone to noise and are placed near the CPU's clock input. High-current circuits and switching circuits are also prone to noise, in the layout of these components or modules should also be away from the logic control circuit and storage circuit, such as high-speed signal circuit, or the module should be away from the logic control circuit and storage circuit and other high-speed signal circuit, if possible, as much as possible to use the control board combined with the The interface is used to connect to improve the overall anti-jamming capability and reliability of the circuit board.
(6) Try to place the decoupling capacitance and filter capacitance around the power supply and the chip. The decoupling capacitor and the filter capacitor are arranged to improve the circuit board electric) as far as possible to place the decoupling capacitance and the filter capacitance around the power supply and the chip. An important measure to improve the anti-jamming ability of the source quality. In practical applications, printed circuit board traces, pin wiring and wiring are in practical applications, printed circuit board traces, pin wiring and wiring are in practical applications may bring a larger parasitic inductance, resulting in the power waveform and signal waveform in the presence of high frequency ripple and burr, and between the power supply and the ground place may result in large parasitic inductance, resulting in high frequency ripple and burr in the power waveform and signal waveform, a decoupling capacitor of 0.1 F can effectively filter out these high frequency ripple and burr. If a chip capacitor is used on the circuit board, it should be if the chip capacitor is used on the board if the chip capacitor is used on the circuit board to close the chip capacitor to the power supply pin of the component. Close the SMD capacitor to the power supply pin of the component. For a power conversion chip, or a power input, it is best to place a capacitance of up to a size of F or greater to further improve the power quality.
(7) Components of the number should be close to the border of the component layout, uniform size, the direction is neat, not with the components, Vias and pads heavy) components should be close to the component's border layout, uniform size, direction neat, stacked. The 1th pin of the component or connector indicates the direction, and the sign of the positive and negative polarity should be clearly marked on the PCB, not allowed to be overwritten; power conversion components (converters, linear transform power supplies and switching power supplies) Linear transform power supply and switching power supply) should have enough heat dissipation space and installation space, the periphery is left with enough welding space and so on. The periphery is left with enough weld space.

 

General principles of PCB Board Component Layout * (RPM)