Amitron Corp.

BLIND & BURIED VIA

BLIND & BURIED VIA

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 reductio

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)