The use of Printed Circuit Boards (PCBs) has become a fundamental part of modern life, but the subject can be daunting for beginners. Our guide aims to demystify the basics of PCBs, allowing individuals to become familiar with the components and materials required to create their own custom printed circuit boards for prototypes or new products.
A PCB, also known as a printed wiring board, is usually a rigid board with electrical circuitry, known as traces, printed onto it. Additional layers and components can be added to create a wide range of designs for different applications. While the basics of printed circuit boards may appear simple, the complexities are quickly noticed once designing begins.
Some terminologies essential for understanding PCBs are:
- Soldermask: This layer acts as a protective coating for the leads to prevent oxidation and safeguard against solder bridges and shorts.
- Silkscreen: This white or colored layer serves as a reference guide and may contain decorative graphics.
- Pads: These are the areas with exposed metal on the board that connect components to the PCB. There are many choices for pad design and connection methods.
- Layers: Even a single layer PCB contains multiple layers of material to function correctly, and PCBs can have two, four, or more conducting layers.
- Footprint: The footprint shows where components will attach to the board, including the location of pads and through-holes.
- Jumper: Insulated or non-insulated pins used as conductors can be incorporated into a PCB design, either to reduce PCB costs or to configure a PCB in different ways.
- Via: A plated hole wall that connects the electrical signal from one layer to another. Thru-hole, blind, and buried vias are different types of vias used in PCB design.
- Copper Traces: These thin copper lines on a PCB act like wires, and they are more precise and faster to create than traditional wiring.
- Annular Ring: The copper ring that encircles a via serves as a contact point for connections between layers.
- Design Rule Check (DRC): A check that ensures a design fits the parameters set for the manufacturing process.
- Gerber File: This industry-standard format is used to save PCB designs and give to manufacturers for production.
With a solid understanding of these basic terms, beginners can begin to develop their skills and knowledge in PCB design.
Classification of Printed Circuit Boards (PCBs)
Printed circuit boards are classified based on various features and designs. Below are some of the ways in which PCBs can be classified:
Classification based on mounting technology:
- Through-hole PCB: Components are connected through the board, providing more stability and durability.
- Surface Mount PCB: Components are soldered onto the surface of the PCB, making them faster and less expensive to manufacture.
Classification based on the number of layers:
- Single Layer PCB: The simplest type of PCB, with only one layer of traces. It is cost-effective and used in applications like calculators and power supplies.
- Double-Sided PCB: Similar to single layer PCBs but with traces on both sides, providing more space for design elements.
- Multi-Layer PCB: With four or more layers, it allows for intricate designs and is commonly used in high-tech applications.
Classification based on flexibility:
- Rigid PCB
- Flexible PCB
- Rigid-Flex PCB
Common PCB Design Software:
- Altium Designer: A professional PCB design software with advanced features.
- KiCad: A free and open-source software for beginners, with a 3D viewer included.
Designing the Electronic Schematic – PCB Basics:
- Consider the assembly process during schematic design to ensure practicality.
- Disassemble and reassemble the circuit digitally to optimize component organization and prevent hot spots.
Designing a printed circuit board layout can be a challenging task, and it’s crucial to organize the structure of your layout properly. After including the basic components in your design, grouping similar components, considering weight distribution, trace length, and heat sinks are vital to optimize the layout of your printed circuit board. It’s normal to experiment with multiple layouts to determine the best option.
When designing a PCB layout, it’s essential to consider some important aspects, such as the schematics, high-frequency signals, routing of signals, and placement of components. The schematic diagram shows how everything is connected and laid out on the PCB. PCB designers who specialize in high-frequency circuits must be diligent about the layout of their boards and consider the many special considerations a high-frequency PCB needs.
The routing of signal and placement of components play a significant role in the heat distribution, weight, performance, and longevity of the PCB. It’s important to create a design that uses best practices to ensure that the PCB works correctly and doesn’t fail prematurely. When designing a printed circuit board, you can infuse your personal style, creativity, and ideas to complement the science behind your design.
As the industry continues to grow and evolve, the possibilities of what you can create with printed circuit boards are limitless. Small volume orders have become affordable, opening up the doors of what used to be an exclusive industry to hobbyists, students, inventors, and entrepreneurs. There is a wealth of knowledge available online for free, allowing anyone to learn and create innovative new products and schematics.
Gerber Labs is committed to catering to this exciting new market by providing support for your success. Our team of engineers and industry professionals is available to answer your questions and ensure that your design is ready for production.
Creating a PCB is a combination of science and art, and there is a wealth of knowledge available for free online to support hobbyists, students, inventors, and entrepreneurs. At Gerber Labs, we love innovation and support your success with a team of engineers and industry professionals ready to answer your questions and ensure your design is ready for production.