PCB Via Is Used To Connect Pads On Two Different Layers

The invention of the printed circuit board or the PCB helped to mount all the active electronic components like resistors, capacitors, diodes, and others at one place. The layers of PCBs increased from one to multiple numbers. The interconnection between the layers was effected by using a PCB via.

When there are too many components to be mounted on a PCB and the area is limited, multiple layers of connections are created on the same circuit board. The multiple layers need some means to connect the various components to a signal and power sources. The connections are provided by the pads.

Pads are the pieces of copper strips that are present in different layers of a multilayered PCB, which act as the connections inside that layer. The connection between pads on the different layers is achieved by using vias. The pads complete the connection between components mounted on the top layer of the PCB.

The construction of a PCB via is accomplished by making a hole between pads on two or more layers of the PCB. A copper tube of the same size as the hole is passed through it. The flanges at the ends of the tube touch the pads to complete the connection.

The connection provided by the PCB via in pad is the easiest way of completing the connection between two layers. These vias can be of various types like blind vias, buried vias, and thermal vias. Only one side of the blind vias is visible. Buried vias cannot be seen from either side of the board while thermal vias are used to draw away the heat from inside a multi-layered board.

The small shiny metallic circles that appear on the upper and lower sides of a PCB are the vias that connect the circuits in the different layers. The pins of the components pass through these vias and are then soldered on the other side.