Different Manufacturing Processes of PCB Pad 2
What are the effects and requirements of different PCB manufacturing processes on the pads? In this article, EPCB summarizes some guidelines for your reference.
8.When designing PCB layout, minimize PCB slotting and openings so as not to affect the strength of the PCB.
9.Valuable components: Do not place valuable components on the PCB corners, edges, mounting holes, slots, cuts and corners of panels. The above positions are the high force areas of the printed circuit board, which can easily cause cracks on soldered joints and components.
10.The heavier components (such as transformers) should not be far away from the positioning holes so as not to affect the strength and deformation of the PCB board. When designing PCB layout, you should place the heavier components under the PCB.
11.Devices like transformers, relays, etc. that can radiate energy should be put far away from devices and circuits that are susceptible to be influenced, such as amplifiers, microcontrollers, crystal oscillators, reset circuits and the like, so as not to affect PCB reliable performance during operation.
12.For QFP ICs (requires a wave soldering process), they must be placed at 45 degrees and add tin.
13.Large area of copper foils requires using heat-insulating tapes attached to the pads. In order to ensure the good penetration of the tin, the component pads on the large-area of copper foil are required to be connected with the pads by means of heat-insulating tapes, and it is not possible to use heat-insulating pads for pads that require over 5A of high current.
14.In order to avoid the phenomenon of misalignment and tombstoning after component reflow process, reflow soldering of pads on both ends of the 0805 and 0805 chip components should ensure heat dissipation symmetry. The width of the connection area between the pad and the printed conductor should not exceed 0.3mm (for asymmetric pads).