In mixed-signal PCB design, there are special requirements for power wiring and the isolation of analog and digital noise from each other to avoid noise coupling, thus increasing the complexity of layout and wiring.
Only when the digital signal is routed on top of the analog portion of the circuit board or the analog signal is routed on top of the digital portion of the circuit board will the interference of the digital signal to the analog signal occur.
The voltage at different points of the same wire may be different, especially when the current is high.
What problems should we pay attention to in PCB laminated design? Let a professional engineer tell you. Two rules must be followed in the design of lamination
Many engineers who are responsible for Process or SMT technology in the factory will often come across solder empty, de-solder or cold solder of the circuit board components and other non-solder problems.
The heat generated during the operation of electronic equipment makes the internal temperature of the equipment rise rapidly. If the heat is not distributed in time, the device will fail due to overheating.
The choice of surface treatment process mainly depends on the type of final assembly components; The surface treatment process will affect PCB production, assembly and final use.
The purpose of the surface treatment is to ensure good solderability or electrical properties. Since copper tends to exist in the air as an oxide and is unlikely to remain as raw copper for long periods of time, other treatments of copper are required.
When PCB size is too large, the printed line is long, the impedance increases, the anti-noise ability decreases, and the cost increases. Too small, the heat dissipation is not good, and the adjacent lines are susceptible to interference.
PCB as the support body of electronic components, its surface needs to be welded components, it requires a part of the copper layer exposed for welding. Hence the need to brush solder resistance paint.
When the copper wire on PCB board is soaked in etching liquid for a long time, it will cause some fine line backing zinc layer to be completely reacted off and separated from the substrate, that is, the copper wire falls off.
The complexity of PCB production process and process maintenance, especially in chemical wet treatment, make it difficult to prevent the surface foaming defects.
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