/How should the wire width and spacing of the pcb be designed?
The width of the printed conductor depends on the current carrying capacity of the conductor and the allowable temperature rise. The thickness of the copper foil plated copper foil is generally 0.02 to 0.05 mm. The different widths printed conductors have different cross-sectional areas too. The conductors with different cross-sectional areas have different current carrying capacity under the condition of limited temperature rise. The larger the area, the larger the current carrying capacity. Moreover, the thinner the wire is, the more difficult to process.
Therefore,wider wires should be appropriately selected under the conditions permitted by the wiring space. If there is a particularly large current, wire should be added for solution. The pattern of the printed conductors and the width of the conductors on the same printed board should be consistent, and the grounding wire can be appropriately widened.
The printed circuit board wire spacing, the length of the parallel segments of the adjacent wires, and the insulating medium determine the insulation resistance between the surface conductors of the printed circuit board. Therefore, the wire spacing should be appropriately increased under the conditions permitted by the wiring.Generally, the wire spacing should be equal to the wire width. The following three factors should be considered in the specific design.
1.The wire spacing of the low-frequency low-voltage circuit depends on the soldering craft of the pcb. The spacing can be smaller for automatic welding, while the spacing can be larger for manual operation.
2.The wire spacing of the high voltage circuit depends on the operating voltage and the anti-electrical strength of the substrate.
3.High frequency circuit board mainly considers the influence of distributed capacitance on the signal.
The wires are connected to the pcb pads and can be performed in the manner shown in figure 1. The wires connected to the rectangular pads are preferably taken from the center of the long side of the pad to avoid a certain angle. When the pad needs to be connected to wider wire, the connection portion of the wire with the pad should be thinned.
① Prepare a actual product surface soldered pcb assembly board . Because printed solder paste and the PCB assembly board without soldering cannot fix the test end of the thermocouple, it is necessary to use the soldered actual product for testing. In addition, the test sample cannot be used repea...
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Pcb prototypes samples need to be aged prior to solderability testing. Because the solderable surface of the component or PCB circuit board that has just been produced is generally not problematic, it will deteriorate due to oxidation after being stored for a period of time. The test must conside...