Methodology for choosing the optimal layout of multilayer printed circuit boards taking into account external mechanical influences

Formulation of the problem. radio-electronic modules on multilayer printed circuit boards (PCB) are characterized by an extremely complex design. When creating such modules, it is necessary to take into account, often extremely contradictory, requirements for the placement of components on the surface, taking into account thermal criteria, requirements for vibration strength and electromagnetic compatibility. Special-purpose radio equipment is often placed in blocks of a "cassette" design, which has a feature in fixing the PCB. Unlike conventional printed circuit boards, in this design, the PCB can only be fixed at the edges, so the placement of components, especially those with a large area, for example, such as microcircuits in BGA, QFP, QFN, PLCC packages, must be given great attention, as this affects mechanical strength and performance of the device.

Purpose. Improving the efficiency of the design process of radio-electronic modules by rational placement of components on the PCB of a "cassette" design. Identification of areas with the highest mechanical stresses and deflections.

Results. It was found that on the PCB of a "cassette" design, when it is fixed only around the perimeter, there are areas with increased deflections, where the installation of components with a large area is undesirable, since this leads to the destruction of the solder joint and the failure of the device. The board can be conditionally divided into nine areas with an aspect ratio of a/4 and b/4, where a, b are the length and width of the board. Experimentally, the most loaded areas of the MPP and areas that have the least impact on the component during external vibration were identified.

Practical significance. A method for placing components on the PCB of a "cassette" design is proposed, which makes it possible to reduce the negative effects of external vibrations and static loads.