The Parts of a PCB
tscircuit represents represents each part of a PCB with a unique Circuit JSON element
Overview
In this tutorial, we’re going to be talking about the different elements that make up a Printed Circuit Board (PCB). For each element, we’ll show different ways that the element can be represented in tscircuit.
What is copper? Why are PCBs green and with yellow parts?
Copper is a conductive material that’s used on a PCB to make an electrical connection between chips. Electricity can move through copper, but not through the green fiberglass part of a circuit board.
A PCB can be thought of as a bunch of “printed” copper separated by green fiberglass sections that “insulate” or don’t conduct electricity. We “glue” chips to
In reality, the copper is chemically etched and there can be different materials separating copper sections, but it’s easiest to think of a PCB as a bunch of printed copper separated by green fiberglass sections.
What are PCB layers?
When you print on a piece of paper, you can print “single-sided” or “double-sided”, PCBs can also be printed singled-sided or double-sided! The “front” of the PCB is called the “top” layer, and the “back” of the PCB is called the “bottom” layer.
We can “print” copper to each of these layers to draw lots of wires and connect lots of chips. Sometimes a wire needs to “go over”/“go under” another wire because the wires aren’t allowed to cross. When this happens, we can use the “back” or “bottom layer” of the PCB to draw the wire so that the wires don’t accidentally touch.
Vias
Vias are holes that connect different layers of PCB. Let’s say you have a chip on the top layer of a PCB and the back layer of a PCB. How can you connect them? The copper on the top needs some way to “pass through” to the bottom layer.
This is where vias come in. A via is a hole that is “filled with copper” so that the top layer can pass to the bottom.
Vias connect different layers of a PCB
Plated Holes
A plated hole is similar to a via but it’s hollow so that you can push metal pins through it. This is important for chips that have big pins that need to fit into holes. Chips with big pins that must go through holes are called “through-hole” chips, and chips with small pins are called “surface-mount” chips.
Unplated Holes “Regular Holes”
Unplated holes or “regular holes” are just holes in the printed circuit board without any copper around them. They don’t electrically connect anything, but can be very helpful for mounting the printed circuit board.
What are inner layers?
Inner layers are layers of PCB that aren’t visible, they’re sandwiched on the inside. Sometimes this is useful when you have a lot of wires to connect and it’s almost impossible to stop them from crossing each other.