PCB printed circuit boards, also known as printed circuit boards, printed circuit boards. Multi-layer printed circuit board, refers to more than two layers of printed circuit board, which is composed of several layers of insulating substrate connection wire and assembly of welding electronic components with the composition of the pad, both with conduction lines, The role of insulation.
PCB multilayer and single-panel, double-panel The biggest difference is the increase in the internal power layer (to maintain the internal layer) and ground plane, power and ground network mainly in the power layer wiring. However, multi-layer board wiring is mainly to the top and bottom of the main, supplemented by the middle of the wiring layer. Therefore, the design of multi-layer board and double-panel design method is basically the same, the key is how to optimize the wiring of the inner layer, so that the circuit board wiring is more reasonable, better electromagnetic compatibility.
Printed board processing, are generally outside the Association processing, so in the Association to provide drawings, must be accurate, as far as possible clear, should pay attention to such as material selection, pressure layer order, thickness, tolerance requirements, processing Technology, etc., should be clear. In the PCB export GERBER, the export data is recommended to use RS274X format, because it has the following advantages: CAM system can automatically enter the data, the entire process without manual participation, to avoid a lot of trouble, while maintaining a good consistency, The
PCB multilayer shelf life in the IPC is defined, the surface process is anti-oxidation, not demolition of vacuum packaging, half a year to use finished, demolished the vacuum packaging in twenty-four hours, and is the temperature and humidity control Environment, the board is not used in the next year to use the packaging, opened within a week to be finished finished film, the same to control the temperature and humidity, gold plate equivalent tin plate, but the control process than tin plate strict.
PCB multilayer board is used in electrical products in the multi-layer circuit boards, multi-layer board with more single-panel or double-panel wiring board. With a double-sided inner layer, two single-sided for the outer layer or two double-sided for the inner layer, two single-sided for the outer printed circuit board, through the positioning system and insulation bonding materials alternately and conductive graphics According to the design requirements of the interconnection of the printed circuit board has become a four-story, six-layer printed circuit board, also known as multi-layer printed circuit board.