Milling is a sloping edge cutting of laminate (execution of the so-called phases), mostly edge joints. In TS PCB, there are two ways to execute this type of machining:
Milling with the depth milling method.
With this method, one can mill almost any edge of PCB. The main limitation is the...
Beside the PCB manufacturers recommendations and guidelines coming directly from customers the requirements concerning embodiment of the printed circuits are also contained in a series of IPC standards, in the IPC 4761 standard among others – which shortly concerns the vias protection.
Due a big variety of functions and applications of printed circuits the different types of the holes can be present in their structure. They can be classified in a general way – metalized / non-metalized or because of their shape or function etc.
The classification considering most ty...
Apart from the basic and temperature parameters listed above, laminates may also be described with electrical parameters (apart from CTI mentioned above), water absorption resistance and CAF.
From the electrical point of view laminate...
For protection against the adverse influence of elevated temperatures laminates with appropriate temperature properties should be used for producing printed boards as they adapt both to the assembly process and to the conditions in which a ready-made device operates.
Definitions of th...
The most basic parameter of a printed circuit is the type of laminate i.e. the base material for production.
Out of all the materials available on the market, it is FR4 i.e. epoxy-glass laminate that enjoys the greatest popularity. It meets the vast majority of needs on the...
If PCBs are made in panels and scoring cannot be performed, PCBs are held using so called bridges.
If the order does not specify their parameters, perforated bridges are normally installed. Keep in mind that the minimum distance of traces, pads, or compound from the perforation hole e...
The commonly accepted file format for printed circuit board designs is the Extended Gerber RS-274X with drilling files in Excellon format.
Most of PCB manufacturers also accept the following file formats:
Eagle BRD (up to 4 layers)
Core, prepreg & copper foil.
Multi-layer printed circuits, when compared to single or double-layer circuits, exhibit a more complex layer structure.
An example stackup is shown in Fig. 1 which presents the layer stack of a typical 4-layer circuit. It is made up of three basic...