When PCB space is limited, or you're working with tight plated through hole constraints, Blind and Buried Vias may be the answer.
Blind & Buried Via technology has played a pivotal role in squeezing more capability into a smaller space. By shortening vias to only pass through necessary layers, more surface area become available for components.
Key benefits include:
- Ability to meet the density constraints of lines and pads on a typical design without increasing the layer count or board size
- PCB aspect ratio reduction
Blind Via is a copper plated hole that connects only one outer layer to one or more inner layers. A blind via never goes all the way through a circuit board. In terms of design, blind vias are defined in a separate drill file.
Additional Benefit of Blind Vias:
Ability to widen BGA breakout channel (layer count reduction)
Buried Via is a copper plated hole that connects two or more inner layers, with no contact with the outer layer. It is impossible to detect a buried via as it is "buried" underneath the outer layer surfaces of a PCB. Buried vias also require a separate drill file.
Additional Benefits of Buried Vias
- No impact to any trace or surface mount component on the top or bottom layers of the board.
- Trace or an SMD pad placement on the outer layers directly over the buried via (added space on outer layers)
Amitron has years of experience in manufacturing PCBs with Blind & Buried Vias. Both our engineers and production facility are equipped to handle the intricacy this technique requires, with very high accuracy. While this technique is more costly, we have seen savings through the reduction of layers or board size. This trend is becoming more and more popular within the PCB industry.