Stack-up is an arrangement of insulating layers and copper. It is done prior to the layout design of the circuit board. In a multilayer Printed Circuit Board (PCB), stack-up layers are silk screen, solder mask, high speed signal layer, signal layer, power plane, and ground layer. Designing a PCB stack-up is one of the most important factors for deciding the performance of a product. Therefore, it goes without saying that choosing the right and experienced manufacturer for designing a PCB stack-up is very crucial. Twisted Traces is a leading manufacturer of PCBs in the US.
Important Factors to Consider for PCB Stack-up
Following are some important factors to be considered for a board stack-up:
- The number of stack-up layers
- The sequence of the layers
- The spacing between the layers
- The types and number of planes (ground and/or power) used
PCB Stack-up Capabilities
We can provide you with different PCB stack-up designs based on your requirements. Following are the standard PCB stack-ups that we provide:
- 4 Layer: As the name suggests, a 4 layer PCB stack-up consists of 4 layer that are spaced at a uniform distance from each other. The internal layers are power and ground, whereas the external signal layers have orthogonal trace routing directions.
- 6 Layer: As far as EMC (Electromagnetic Compatibility) is concerned, a 6 layer PCB stack-up is preferred over a 4 layer one. Typically, a 6 layer PCB stack-up consists of two planes and four signal routing layers.
- 8 Layer: The EMC performance of an 8 layer PCB stack-up is better as compared to that of a 4 or 6 layer stack-up. An 8 layer PCB stack-up consists of four planes and four wiring layers.
- 10 Layer: When you require six routing layers, a 10 layer PCB stack-up is used. A 10 layer PCB stack-up consists of four planes and six signal layers. It is the highest number of layers than can be fabricated conveniently in a board of 0.062″ thickness.
The number of layers should be finalized only after taking into account the following:
- The cost and number of signals to be routed
- Whether the product meets Class A or Class B emission requirements
- Whether the PCB is in a shielded or unshielded enclosure
- EMC engineering expertise of the PCB designer