Almost all printed circuits are required to be printed on the PCB circuit board, with names to identify components, circuits, test points and the printed board itself. The circuit board factory also attaches great importance to this aspect. With curiosity, we walked into the circuit board factory to learn about the little knowledge related to printed circuit marking and identification.
In PCB circuit board manufacturing; the name can be printed after the printed board is etched, or etched out at the same time as the circuit is etched. If it is printed later, it is usually screen printed or stamped. In either case, in order to ensure electrical and chemical properties, the marking material must be carefully. Considering this principle and the extra process steps involved, usually the designer has the name on its photographic base and etches it at the same time as the circuit is etched. Although these names are conductive; in general he will not cause a problem and the writing of the name should be small enough to withstand etching and still be clearly visible. The thickness of the copper foil, the location of the name relative to the wire will determine how much damage the name will suffer when etched. When using 2 oz. 3 oz. copper foil, the name is too small to read clearly.
In order to facilitate testing and maintenance - a printed board assembly and to facilitate visual inspection of the assembly against the drawing information, the reference designation of the component should be considered. The polarity of capacitors and diodes should be indicated in addition to the reference designation marking, which should be marked as close as possible to its mounting hole. The reference designation and polarity should be fully visible where the component is placed. DIP ICs should always be marked with lead 1, and TO-5 ICs with leads 6, 8, 10, or 12 should also be marked.
Printed circuit boards should have two identification marks of different nature, because before the electrical components are assembled, the manufacturer has to machine and plate the printed board, it needs to use documents and needs a method to identify the printed board. One is the manufacturing drawing number (original drawing number) of the printed PCB circuit board, and the other is the number of the printed PCB circuit board assembly. It should also be marked on one side of the component. , and is usually tested and repaired here as well. Numbering should always be continued with "ASSYNO". In addition, the PCB assemblies must be numbered consecutively for lookup, and if space permits, your company name can be displayed on the PCB. All these requirements are easy to do with etched foil.
