The Difference between Footprints and Land Patterns

The design of printed circuit board is not only related to creation of schematics and its layout but there are numerous other terminologies which must be understood. Such as the symbols are abstracting functions of different components and are communicating as the interface among both schematic reader and software. Therefore, to this point, there is a need of definition of the connecting points for entire schematics with points referred as pins. Certain artwork is also introduced in to the symbols for its effective utilization. The simplest symbol of all is known as the black box symbol and it is merely surrounding the symbol through box in which each pin is having a meaningful name. For a few of the symbol classes, there are certain standards defining the outlook of such symbols. Some of the standards of the symbols are incompatible to each other, therefore you have to be inspired of the standard which is best suiting your purpose.

Footprints and Land Patterns

Footprint and Land Patterns

The footprint is defined as the physical interface among components or land pattern and printed circuit boards which is also comprising of the information of documentation such as reference, polarization mark, and outline. The land patterns are either derived from the dimensions of the component’s tolerances included or taken from the datasheet. This all is as per the standards of industry. Most probably the land patterns are also derived from same standard. It must have all of the connection points which are known as pads for soldering all of the components over sit. The size, position, and shape of the pads must be aligned with the specifications of the datasheet for avoiding faults.

 

The pads are defining the features to be appearing on the paste layer, masks, and copper. The copper is known as the area which is covered by copper layer. Masks are the cutout region over the layer of solder mask, whereas paste the region of cutout over solder paste stencil which is utilized for the reflow soldering. The courtyard area is where none of the components are to be placed. The courtyard area is usually very large than that of combined parts body and pads area.

 

It is considered as beneficial when having an outline for the pins and component body over the silk screen for de-bugging and soldering. However, it must be made sure that all of this must be visible after the process of assembly i.e. the outline of silk must be larger than that of the body of components. The layers of fab over the artwork is very beneficial in case if you need the documentation on the board. However, in such a case, it must be having the entire outline of the body including the pin markers.

Footprints and Land Patterns

Both terms footprint and land patters are usually utilized interchangeably in the printed circuit board assembly process in the industry. While, both terms are quite similar to each other, however, still there lies a nuance which is drawing a differentiation among both terms. Sometimes, it is said that the differentiation among both terms is somehow pedantic, however the truth lies that more often the functionality of both terms is different after understanding it. It is a fact that certain component might have dissimilar land pattern however it is going to have a single footprint always.

 

The footprint of a component is officially referring to the actual physical size of that specific component. Therefore, if you are to measure the leads and body thoroughly of certain given component and drawing a picture through utilization of the dimensions, then you may have the part of the footprint. To picturize the concept in a more relevant way, the footprint of any component is much similar to the footprint of a human or person as it is imprinting the component’s print if pressed down through hands.

 

The land pattern is referring to the size of the pads and its outline for a given component or part of the printed circuit board that must be designed. Both of the automated and manual processes of soldering is requiring that the designed pads for all of the parts of the printed circuit board must be larger than its leads where these components are supposed to be soldered. This is to make it possible for the land patterns to be slightly larger than that of the footprint of every component. The datasheets of manufacturers are mostly having the required information of the land patterns.

 

 

Services of RayPCB

Among the highly appreciated aspects of the RayPCB, one of the aspects is its service of thorough DFM check of comparison of land pattern vs. footprint. Before the process of fabrication to begin, the expert engineers of RayPCB are checking the quality management and is comparing the land patterns of each and every part of the design which that of the dimensions of documented footprint for making it sure to have a higher quality assembly process of printed circuit boards. This service of RayPCB is anticipating many of the common defects that incur while manufacturing process of printed circuit boards because of dissimilarities among the footprints and land patterns.

 

Therefore, if you have queries regarding footprints and land pattern associated to the design, fabrication, and assembly process of your printed circuit board, please feel free to contact our customer service agents who are available to serve you 24/7 a day. You can visit our website online and then go to contact us form, filling your query related information and our customer representative will soon contact you with the best possible solution. You can either call on our toll-free number mentioned on our website to contact a customer representative immediately and seek help regarding your confusions. Moreover, you can also email us your queries giving details of the problem or question that you are facing. We will give a detailed response of your email giving you satisfactory answers to your questions. We are always looking forward sharing a friendly bond with our customers which bring them back to us in future for more projects.