The cause of electroplate cavity in circuit board and how to prevent it
For any printed circuit board design with two or more circuit layers, electroplated through-holes form an electrical interconnection between the different layers.
For any printed circuit board design with two or more circuit layers, electroplated through-holes form an electrical interconnection between the different layers.
Once a PCB laminate problem is encountered, it should be considered to add to the PCB laminate material specification.
the traditional physical plate making method is labor-intensive, time-consuming and has low precision, while the chemical rapid plate making method has a controllable precision, but the process is complicated and unfavorable to environmental protection. B
The following introduces common circuit board analysis methods: 1, AC equivalent circuit analysis method, 2, frequency characteristics analysis method, 3, DC equivalent circuit analysis method, 4, time constant analysis
Power supply noise is directly or indirectly generated from the power supply, to prevent the influence of power supply noise on the circuit, but also to minimize the influence of the outside world or circuit on the power supply.
In the era of HDI high-density connection technology, the line width and line distance will inevitably become smaller and denser, and thus a different type of PCB structure is derived.
We call PCBS single panel. Because a single panel has many strict restrictions on the design circuit (because there is only one side, the wiring can not cross and must go around a separate path)
Mobile terminal with HDI board is the main point of PCB growth. The mobile terminal represented by smart phone drives HDI board higher density and thinner. PCB all to high density fine line development, HDI board is particularly prominent.
Many parameters in the circuit are adjusted by software. The margin of some parameters is too low and in a critical range. When the machine is running in line with the reason for the software to determine the fault, then the alarm will appear.
Through the hole plug oil process is one of the hole treatment methods, the first is to opaque, above must have ink cover, plugging; The second is the hole can not appear yellow phenomenon, and do not touch tin.
Board bubbling is one of the most common quality defects in PCB production. Because of the complexity of PCB production process and process maintenance, especially in chemical wet treatment, it is difficult to prevent board bubbling defects.
The abnormal quality of PCB board will cause direct losses to customers and PCB manufacturers. The loss of copper wire is one of the abnormal quality phenomena, but this kind of abnormal will cause greater losses to PCB manufacturers.