Via (electronics) facts for kids

A via is like a tiny, super-important tunnel or pathway that connects different layers inside a circuit board. Imagine a circuit board as a multi-story building for electronic parts. These parts need to talk to each other, even if they're on different floors (layers). Vias make sure electricity can flow from one layer to another, allowing all the parts to work together.

What is a Printed Circuit Board?

A printed circuit board, often called a PCB, is a flat board made of a special material that doesn't conduct electricity. On this board, there are lines or "traces" made of copper that act like tiny wires. Electronic parts like chips, resistors, and capacitors are attached to the PCB. These parts need to be connected to each other to make an electronic device work, like your phone or computer.

Why Do PCBs Have Layers?

Modern electronic devices are very small and powerful. To fit all the necessary parts and connections into a tiny space, PCBs are built with multiple layers, stacked on top of each other. Think of it like a skyscraper: you can fit many offices in a small area by building upwards. Each layer of a PCB has its own set of copper traces and components.

How Vias Connect Layers

A via is essentially a small hole drilled through the PCB. The inside of this hole is then coated with a conductive material, usually copper. This copper lining creates an electrical connection between the copper traces on different layers of the board.

Different Kinds of Vias

While there are many types, the most common via goes all the way through the circuit board, connecting traces on the top, bottom, and any layers in between. These are called through-hole vias. When you look closely at a circuit board, you might see many tiny, shiny circles – these are often through-hole vias! They are essential for making sure all the electronic parts can communicate and work together correctly.

Images for kids

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  Cut section of a multilayer via, showing the connection between layers.

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  A circuit board where the small metallic circles are vias, connecting different parts.