How PCBs Are Made: From Blank Board to a Smart Gadget

If you’ve ever wondered how your gaming mouse, keyboard, or even your phone works, the answer usually starts with a PCB, or Printed Circuit Board. Basically, it’s the flat board that holds all the electronic components and connects them so electricity can flow the right way.

But how does a plain blank board become the intelligent mind behind your devices? Let's go through it.

Step 1: Designing the PCB

Engineers first design the PCB on a computer using a program like Eagle, KiCad, or Altium before anything gets produced.

• They sketch out the circuit paths, essentially tiny roads for electricity.
• They also indicate where components such as resistors, LEDs, and microchips will be located.
• This layout is stored as an electronic file named Gerber files, which the factories use to fabricate the actual board.

Step 2: Board Printing

PCBs typically begin life as an empty board of fiberglass with a thin layer of copper at the surface.

• The copper is where electricity travels.
• The factory brings the circuit pattern onto the copper through photolithography or screen printing, similarly to creating a stencil for spray paint.

Step 3: Etching

Etching is a process that takes away unwanted copper.

• They apply chemicals to dissolve all the copper that is not part of the circuit.
• What is left are the copper paths from the design, which connect where components will sit.

Step 4: Drilling & Plating

• Small holes are drilled into the board for components' legs or to link several layers of copper.
• The holes are plated with copper so electricity can flow through them.

Step 5: Applying the Solder Mask & Silkscreen

• Solder mask – The green (or occasionally red/blue) paint you find on PCBs. It covers up the copper and stops short circuits by accident.
• Silkscreen – White writing and symbols printed onto the PCB to indicate where the components belong. Extremely useful if you're assembling or repairing electronics.

Step 6: Adding Components

Time to put resistors, capacitors, ICs, and all the rest in. Read more about these on on this blog.

• Components are either soldered by hand or added by a machine named Pick and Place.
• Soldering ensures the parts adhere and allow electricity to flow correctly.

Step 7: Testing

A PCB is tested before it's shipped out to ensure electricity flows well and all components function.

• They use equipment or even basic tools to test for short circuits or broken pathways.
• Only test-passing boards are sent to be used in your devices.

Written in smaller sentences for the lazy ones

1. Design – Create the circuit on a computer.
2. Print – Transfer the design on a copper board.
3. Etch – Cut away unwanted copper.
4. Drill & Plate – Drill holes and connect plates.
5. Solder Mask & Silkscreen – Coat the board and indicate spots for components.
6. Place Components – Put all of the electronic components in.
7. Test – Ensure it functions.

PCBs are ubiquitous — from your gaming computer, smartphone, to LED bulbs in your home. Without them, modern electronics would not even exist!