28.09.2017
Milling of circuits edges – definition, methods of chamfering
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...
10.08.2017
Vias types according to IPC standard
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.
&nbs...
04.08.2017
PCB elements: HOLES TYPES
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...
28.07.2017
Parameters of printed circuits _ ELECTRICAL
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.
Electrical characteristics:
From the electrical point of view laminate...
19.07.2017
Parameters of printed circuits _ TEMPERATURE
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...
07.07.2017
Parameters of printed circuits _ BASIC
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...
28.06.2017
Bridges – structure and parameters
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...
25.05.2017
Accepted file format for printed circuit board designs
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:
Gerber RS-274X2
ODB++
Eagle BRD (up to 4 layers)
Mania-Barco...
06.04.2017
Construction of multi-layer PCB's
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...