PCB board manufacturing technology, including computer-aided manufacturing processing technology, that is, CAD / CAM, and light painting technology.
Computer-aided manufacturing (CAM) for a variety of processes according to the process. Various process requirements, are to make the necessary preparations before the light painting. For example, mirroring, solder resist expansion, process lines, process boxes, line width adjustment, center hole, profile line and other issues to be completed in
CAM work: the correction of the size of the pad, combined D code. Correction of line width, combined D-code. Minimum pitch check, pad to pad, pad to line, line to line. Aperture size checking, merge splicing. Minimum line width check. Determine solder resist expansion parameters.
Perform mirroring. Add various process lines, process boxes. Performs line width correction to correct side etching. Forms the center hole. Add profile corner lines. Add positioning holes. Piecing, rotating, mirroring. Piecing pieces together. Overlay processing of graphics, cut corner and cut line processing. Add user logo.
Expanded Information
PCB size is too large, the printed line is long, the impedance increases, the anti-noise ability to decline, and the cost increases; too small, the heat dissipation is not good, and the neighboring lines are susceptible to interference. After determining the PCB size, then determine the location of special components. Finally, according to the functional unit of the circuit, the layout of all the components of the circuit.
In determining the location of special components to comply with the following principles:
1, as far as possible to shorten the connection between high-frequency components, and try to reduce their distribution parameters and electromagnetic interference with each other. Components susceptible to interference can not be too close to each other, input and output components should be as far away as possible.
2, some components or wires may have a high potential difference between the distance between them should be increased to avoid the discharge of accidental short-circuit. Components with high voltage should be arranged as far as possible in the commissioning of the hand is not easy to reach the place.
3, weight more than 15g components, should be fixed with a bracket, and then welded. Those large and heavy, heat generating components, should not be mounted on the printed circuit board, but should be mounted on the chassis of the machine on the floor, and should consider the heat dissipation problem. Thermal components should be kept away from heat-generating components.?
4, for potentiometers, adjustable inductor coil, variable capacitors, microswitches and other adjustable components of the layout should be considered the structural requirements of the machine. If it is adjusted in the machine, it should be placed on the printed circuit board where it is convenient to adjust; if it is adjusted outside the machine, its position should be compatible with the position of the adjustment knob on the chassis panel.
Baidu Encyclopedia - PCB
Baidu Encyclopedia - Circuit Board