When component placement, to separate incompatible elements arranged to ensure interference between components, keeping in mind the following questions: When component layout to meet the mechanical structure of the positioning system, to be strictly positioning devices such as sensors, transformers, monitors and other fixed position, the heating element to install a heat sink and away from integrated circuits, placed at the edge of the PCB, because at high frequencies, PCB board lead, vias, distributed capacitance greater impact on the circuit, so to minimize design time Small traces from interference generated by the power supply is more serious, the integrated circuit chip decoupling capacitor placement is preferred form, this leads short little disruption. Board type and component selection, after the layout is good, you want to consider is the circuit board wiring problems, the principle is the cable as short as possible. Introduction of an additional signal in order to reduce interference, generally the first clock distribution line, a signal line sensor, high-speed signal line and then the cloth, the cloth generally unimportant last signal line considering the case of the above principles also note problems: the multilayer wiring board when taken between two adjacent well-shaped wiring structure, to reduce the bending of the connection in order to prevent changes in the resistance value, the signal line is designed arc-shaped bend. PCB board wires or devices from the outermost edge of the board to leave a distance of not less than 2mm conducive fixed PCB board and prevent changes in impedance values conducive to short fine wire interference, taking into account the resistance and flow through the wire current conductors typically meet the requirements of a width between 1 ~ 1.5mm.
Electronic components can be divided into discrete components and integrated components, integrated components of choice when designing electronic systems, as integrated components tightness, joints less interference line is strong, select signal slope slower devices can reduce the high frequency components impact on the circuit, using SMD components to shorten the distance connecting wires, reducing the impedance values, help to improve the electromagnetic compatibility.
