The most common PCB component selection mistakes to avoid
o-leading.com
o-leading.com
2017-06-28 10:47:34
Just like any other electronic components, PCB components are rapidly undergoing fast technological advancements in both size and performance. This is attributed to the invention of the Integrated Circuits, microcontrollers and chips in the market such that the flexibility of PCB components increases significantly. On the other hand, one might think that the process of component selection for your PCB is very simple and obvious. However, there are many considerations and technical properties that one should take keen notice of. This is because an error made in the selection of components can lead to serious damages hence the ineffectiveness of the PCB.
1.Not using reference designators
Failure to number reference designators might complicate the process of reviewing the BOM and at the same time prevent accurate sorting. This might result in wrong PCB component selection.
2.Forgetting to review the BOM
Reviewing the Bill Of Materials report is necessary for your PCB design since the manufacturer can put the PCB manufacture on hold until some parts are provided or specified. The BOM should be a clear representation of the total cost of your PCB design and all components to be used should be shown in the BOM and their respective prices.
3.Failing to check for virtual part footprints
In the schematic drawing phase, you should consider having land patterns and footprints that have to be made in the PCB layout phase. Careful PCB component selection is crucial during this stage. Some of the major considerations one should take care of are:
Always remember that footprints are comprised of mechanical dimensions (X, Y and Z) of the part and electrical pad connections. This includes the body outline and the pins attached to the PCB. When selecting PCB components, it is crucial to consider packing restrictions on both the bottom and the top sides of the PCB. The choice of components might change during PCB design thus selection of the parts to undergo PTH and those to undergo SMT in the initial design stages is crucial.
4.Inadequate ground planes and bypass capacitors
Just like a resistor, a capacitor is a passive PCB component which depends on external power sources to operate. On the other hand, a ground plane is an electrically conductive surface which is connected to an electrical ground. When selecting the components for your PCB needs, it is crucial to ensure that it has enough bypass capacitors for use in power regulation and ground planes for use in appropriate IC pins. Failure to do this leads to a PCB circuit with non-optimized electromagnetic compliance and inefficient performance.
5.Failing to ensure that components fit in the packaging after PCB assembly
Selecting PCB components might be hectic but this process should be carried out professionally so that your PCB functions as expected. However, one should not forget to consider how the components fit in their packaging so that a functional and a non-compromised design are achieved. The height clearance height of the components should be considered before design. This can be best achieved by drawing a basic board shape outline in the early design but taking care to place the larger components on the best suited location on the board to allow for quick visualization of the position of the components and the best PCB components to be selected.
6.Not verifying spare gates
All spare gates should have inputs connected to a signal to prevent the floating of the inputs. One should always ensure that they review the spare gates and the unconnected inputs. This is because the process of debugging is more complicated when compared to simply reviewing the gates. It is vital to recall that if the inputs are left to float, the system might not operate effectively. Components should, therefore, be selected in a way that there is a complete connection between all the inputs and the outputs of the PCB.
Careful selection of PCB components is paramount to aid in averting challenges like non-functional end PCBs. So choose our pcb manufacturer in china and enjoy our explicitly unique services.