What are some of the benefits and downsides of moving from a two layer PCB with components on a single side, to a four layer PCB with components on both sides?

We got a quotation sheet of four layers board but it greatly exceed our budget. So now we are thinking about reduce layers to save cost. Does this solution work?

PCB Design
October 8, 2023

Two-layer is cheaper, while the four layers will cost more. Because

There are twice as many layers to etchand then laminate.
It will take almost twice as much work, steps and materials to fabricate.
It will also take two assembly passes for pick and place instead of one.
Anything manually placed through hole will also take one more pass for the second size.

Only drilling and 2 silkscreen and 2 solder resist will remain the same.

Compared to four layers, double sided

will allow a significant gain in component density.

Primary side	taller stuff, large scale ICs and connectors
Secondary side	low profile passives (chip resistors & capacitors) and perhaps low profile ICs and diodes, signal transistors

That will allow a smaller PCA footprint, so the PCA costs are saved in enclosure and overall size. Thus, the user-friendly weight of PCB will suit portable equipment.

#PCB Design

Oliver Smith

Oliver is an experienced electronics engineer skilled in PCB design, analog circuits, embedded systems, and prototyping. His deep knowledge spans schematic capture, firmware coding, simulation, layout, testing, and troubleshooting. Oliver excels at taking projects from concept to mass production using his electrical design talents and mechanical aptitude.

Oliver Smith

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