Intro to Printed Circuit Boards




Intro to Printed Circuit Boards

In this instructable, I’ll go over what a printed circuit board is, where they are used, and the basics of how to make one yourself. So sit back, strap in, and enjoy learning about this very important and interesting method of making electronics!

Note: this is an introductory guide. I’m sure that there is a lot I did not cover, and if you find something you think I should mention in this guide, make sure to put it in a comment below!
Step 1: Creating Circuits
Picture of Creating Circuits

When creating a circuit, you need to connect multiple electronic components together, usually to perform some useful function. There are many different ways to do this:

Breadboard
A common method of prototyping circuits.
Pros
Great for building temporary circuits and some quick projects.
Quick and Easy
Cons
Very impermanent; wires and components can easily be pulled off
Restricted to through-hole components

Point to point
(solder components directly to each other)
Pros
Don’t need a board for your projects
Quick construction
Can take up less space
Cons
Not very organized
Hard with small components
Difficult to repair
Wire Wrap
Use board of pins and wrapped wires for connections
Pros
Fast if you have the tools and materials and a simple circuit
Cons
Can be very disorganized
Difficult to repair
Proto-board
Plated or non-plated holes in fiberglass for circuit construction
Pros
More organized than point to point
Can be easily mounted in a case
Can have relatively quick construction
Cons
Labor intensive to make circuits
Conductive Ink
Ink with a very low resistance that can be painted on and used as a circuit
Pros
A cool, novel way of making circuits
Good to get kids interested in making simple circuits
Cons
Not very practical
Cracks easily
Low conductivity
Conductive Thread
Similar to conductive ink: cool and novel, not too practical in most cases. However, some cool uses in wearables!

READ  Easy IoT weather station with multiple sensors

And finally, Circuit Boards!
Step 2: What is a Printed Circuit Board
Picture of What is a Printed Circuit Board

A Printed Circuit Board (or PCB for short) is a different way of connecting electrical components together. It is made out of a non-conductive material, usually fiberglass. However, there is a layer or multiple layers of copper over the board, which lets you connect components when the copper is etched away in the correct patterns.

The board in the image above was made with a CNC machine which mechanically removed a copper layer in specific places to allow components to be soldered on and through the board, and be connected together in the right way. While this one isn’t, many are then coated with a solder mask of a certain color, often green (but not always) that helps solder stick to the right places.

PCBs are great for creating circuits because they are:

Inexpensive
Can be mass produced
Reliable
Are the industry standard

PCBs are in almost everything electronic; computers, mice, electric scooters, refrigerators, screens, phones, and countless other devices.

The world market for printed circuit boards (PCBs) reached an estimated $60.2 billion in value in 2014, and is only growing larger: http://www.iconnect007.com/index.php/article/9297…
Step 3: Designing a PCB
Picture of Designing a PCB

The first step to designing a PCB is knowing what you want to make. There can be a lot to designing a PCB, or it can be extremely simple; it completely depends on what circuit you’re making.

But whatever you end up making, it’s helpful to have a program to organize it all for you and give you the tools you need to turn a schematic (abstract diagram of all the parts and connections you need) to a final layout for your circuit board. From there, you export your file and can send it off to be fabricated.

READ  10W STEREO AUDIO AMPLIFIER

Some programs for PCB Design:

Altium
KiCad (free)
CadSoft Eagle

All these programs are designed to do the same thing; help you make your PCB. Some things you will need to create:

A board shape to define how large and what shape your board is

Component placement: where are your parts?

Trace routing: these connect all your components

File Export: export industry standard gerber files for manufacture

There’s also lots of other circuit components your board could have, some of which I’ll briefly list here to help spur your imagination:

Vias: connect traces to multiple layers of copper
Through holes: for parts with leads
Surface mount pads: to connect surface mounts parts
Ground/Power planes
Test points
Holes/slots
Integrated antenna
Multiple layers

Step 4: Want to make a PCB?
Picture of Want to make a PCB?

So you want to make a PCB? Well good, there’s tons of different methods you can use.

Fab House

Probably the most effective and easiest way is to send your gerber files to a fab house. These take the files you created in your circuit creation program and fabricate a board for you. I’ll go over these a bit more in the next step.

CNC Machine

You can also use a CNC machine to create your board if you have access to one. I’ve personally used a machine at work made by LPKF, which is specifically designed for making circuit boards and the Othermill by Other Machine Co. The Othermill is designed for hobby grade CNCing, and can carve out 3d shapes into blocks of soft material or mill away a double-sided copper clad board to create a PCB.

READ  SCROLLING TEXT CIRCUIT LED MATRIX PIC16F628 74HC595

Chemical Etching

Finally, the cheapest of the three; etching your own board at home with multiple stages of chemicals to eat away the areas inbetween the traces. I’ll leave it an exercise to the viewer to find out how this interesting process works: http://www.instructables.com/howto/etch+PCB/
Step 5: Getting PCBs Made
Picture of Getting PCBs Made

A popular option for getting PCBs is to have them made by a fab house. These are professional facilities that handle construction of possibly thousands of boards a day. Each fab house is of varying quality and has different tolerances of trace width, hole size, and other specificities like cutting slots so you should do your research before sending your files out anywhere.

Some places will have discounted shipping but longer lead times, or only offer smaller batches so are good for prototypes but not when you need a lot of boards. Everyone has their preference for places and it’s up to you to choose which place to use. Here are a few:

Alberta Printed Circuits (APCircuits.com)

Advanced Circuits/4pcb.com/Barebones PCB/33Each.com/FreeDFM.com

E-TekNet

Gold Phoenix

Olimex

OurPCB

PCB123/PCB Express

Sierra Proto

PCBCart

And due to popular demand: http://pcbshopper.com/

PCB Shopper lets you compare multiple different fab houses and determine what place is right for your needs.

More info: http://www.ladyada.net/library/pcb/manufacturers.h…

(note: old article)

Image: https://www.element14.com/community/servlet/JiveSe…

For More Details: Intro to Printed Circuit Boards




Leave a Comment

*
= 4 + 5

Read previous post:
Programming 16-Bit PIC Microcontrollers in C
Programming 16-Bit PIC Microcontrollers in C By Lucio Di Jasio E-Book

Book Introduction: New in the second edition: * MPLAB X support and MPLAB C for the PIC24F v3 and later...

Close
Scroll to top