What is a Single-Sided PCB?
A single-sided PCB, also known as a one-layer PCB or Single-Layer PCB, is a printed circuit board that has conductive copper traces on only one side of the board. The other side of the board is left bare, usually with a solder mask coating to protect against oxidation and provide a surface for labeling.
Single-sided PCBs are the simplest and most cost-effective type of PCB. They are commonly used in low-complexity electronics projects and products where cost savings is a priority.
Advantages of Single-Sided PCBs
- Low cost – Single-sided PCBs are the least expensive type of PCB to manufacture due to their simple construction.
- Ease of fabrication – With traces on only one side, single-sided PCBs are relatively easy to fabricate, even for hobbyists and small-scale producers.
- Simplified assembly – Components are mounted on only one side of the board, simplifying the assembly process.
- Suitable for low-complexity circuits – Many simple electronic projects can be implemented using a single-sided PCB.
Disadvantages of Single-Sided PCBs
- Limited circuit complexity – With traces on only one side, single-sided PCBs are limited in the complexity of circuits they can accommodate. More complex designs may require a double-sided or multi-layer PCB.
- Larger size – To avoid overlapping traces, single-sided PCBs may require a larger board size compared to a double-sided PCB with the same circuit.
- Potential for electromagnetic interference (EMI) – With traces exposed on one side, single-sided PCBs are more susceptible to EMI compared to boards with ground planes.
When to Use a Single-Sided PCB
Single-sided PCBs are suitable for a variety of low-complexity electronics projects and products, such as:
- Simple Arduino projects
- LED lighting circuits
- Basic Sensor Circuits
- Low-frequency analog circuits
- Educational and hobby projects
When deciding whether to use a single-sided PCB, consider the following factors:
- Circuit complexity – If your circuit is relatively simple with few components and no overlapping traces, a single-sided PCB may be sufficient.
- Cost – If cost is a primary concern and your circuit can be implemented on a single-sided board, it is often the most economical choice.
- Production scale – For small-scale production or one-off projects, the simplicity of single-sided PCBs can be advantageous.
Designing Single-Sided PCBs
When designing a single-sided PCB, there are several key considerations to keep in mind:
Component Placement
- Place components strategically to minimize the number of traces and avoid overlapping.
- Consider the flow of signals through the circuit and place components accordingly.
- Leave adequate space between components for traces and to facilitate soldering.
Trace Routing
- Route traces carefully to avoid overlapping and minimize trace length.
- Use 45-degree angles instead of 90-degree angles to reduce electromagnetic interference.
- Maintain appropriate trace width based on the current carrying requirements of the circuit.
- Keep high-frequency and sensitive traces away from potential sources of interference.
Jumper Wires
- In some cases, it may be necessary to use jumper wires to create connections that cannot be made with traces on a single side.
- Jumper wires should be kept as short as possible and placed strategically to minimize their impact on the circuit.
Solder Mask and Silkscreen
- Apply a solder mask to the non-component side of the board to protect against oxidation and provide insulation.
- Use silkscreen labels to clearly identify components, connectors, and other features of the board.

Manufacturing Single-Sided PCBs
PCB Fabrication Process
The fabrication process for single-sided PCBs typically involves the following steps:
- Substrate preparation – The substrate, usually FR-4 laminate, is cut to the desired size and shape.
- Copper lamination – A thin layer of copper foil is laminated onto one side of the substrate using heat and pressure.
- Photoresist application – A layer of photoresist is applied to the copper surface.
- Exposure and development – The photoresist is exposed to UV light through a photomask, then developed to remove the unexposed areas.
- Etching – The exposed copper is etched away using a chemical solution, leaving only the desired traces.
- Photoresist removal – The remaining photoresist is stripped away, leaving the final copper traces.
- Solder mask application – A solder mask is applied to the non-component side of the board and cured.
- Silkscreen application – Silkscreen labels are applied to the component side of the board.
- Surface finish – A surface finish, such as HASL or ENIG, is applied to the exposed copper to protect against oxidation and facilitate soldering.
PCB Manufacturing Costs
The cost of manufacturing single-sided PCBs depends on several factors, including:
- Board size and shape
- Number of boards ordered
- Copper weight and thickness
- Surface finish type
- Special requirements, such as controlled impedance or tight tolerances
In general, single-sided PCBs are the least expensive type of PCB to manufacture. The following table provides a rough estimate of the cost per board for various quantities and sizes:
Quantity | 5 cm x 5 cm | 10 cm x 10 cm | 20 cm x 20 cm |
---|---|---|---|
10 | $5 – $10 | $10 – $20 | $20 – $40 |
100 | $1 – $2 | $2 – $4 | $4 – $8 |
1000 | $0.50 – $1 | $1 – $2 | $2 – $4 |
Note: These prices are rough estimates and may vary depending on the specific manufacturer and requirements.
Assembling Single-Sided PCBs
Soldering Techniques
Soldering components to a single-sided PCB can be done using either through-hole or surface-mount techniques.
Through-Hole Soldering
- Insert component leads through holes drilled in the PCB.
- Apply solder to the lead on the opposite side of the board, creating a mechanical and electrical connection.
- Trim excess lead length.
Surface-Mount Soldering
- Apply solder paste to the pads on the PCB using a stencil or syringe.
- Place components onto the pads, aligning with the solder paste.
- Reflow the solder paste using a reflow oven or hot air soldering station, melting the paste and creating a connection.
Inspection and Testing
After assembly, it is important to inspect and test the PCB to ensure proper functionality:
- Visual inspection – Check for proper component placement, solder joint quality, and any visible defects.
- Continuity testing – Use a multimeter to verify that connections are properly made and there are no short circuits.
- Functional testing – Power on the board and test its functionality to ensure it performs as expected.
FAQ
1. Can I make a single-sided PCB at home?
Yes, it is possible to make single-sided PCBs at home using a variety of methods, such as toner transfer, photoresist, or CNC milling. However, the quality and reliability of home-made PCBs may not match that of professionally manufactured boards.
2. Are single-sided PCBs suitable for high-frequency circuits?
Single-sided PCBs are generally not recommended for high-frequency circuits due to their lack of a ground plane and potential for increased electromagnetic interference. For high-frequency applications, a double-sided or multi-layer PCB with proper grounding and shielding is typically required.
3. Can I use a single-sided PCB for a circuit with a microcontroller?
Yes, simple microcontroller circuits can often be implemented on a single-sided PCB. However, more complex designs with many peripherals or high-speed signals may require a double-sided or multi-layer board.
4. How do I choose the right copper thickness for my single-sided PCB?
The choice of copper thickness depends on the current carrying requirements of your circuit. Thicker copper can carry more current but is more expensive. Common copper thicknesses for single-sided PCBs include 1 oz (35 µm), 2 oz (70 µm), and 3 oz (105 µm).
5. What surface finishes are available for single-sided PCBs?
Common surface finishes for single-sided PCBs include:
– HASL (Hot Air Solder Leveling) – A thin layer of solder is applied to the exposed copper, providing a solderable surface.
– ENIG (Electroless Nickel Immersion Gold) – A layer of nickel is plated onto the copper, followed by a thin layer of gold, providing a flat, solderable surface with good shelf life.
– OSP (Organic Solderability Preservative) – A thin, organic coating is applied to the copper to protect against oxidation and provide a solderable surface.
Conclusion
Single-sided PCBs offer a cost-effective and simple solution for low-complexity electronics projects and products. By understanding the advantages, limitations, and design considerations of single-sided PCBs, you can make informed decisions about when and how to use them in your projects.
When designing and manufacturing single-sided PCBs, pay close attention to component placement, trace routing, and the use of jumper wires to ensure a functional and reliable board. Proper soldering techniques and thorough inspection and testing are also critical to the success of your project.
While single-sided PCBs are not suitable for every application, they remain an important tool in the electronics industry, particularly for simple, low-cost projects. As you gain experience with single-sided PCBs, you’ll be better equipped to tackle more complex designs and move on to double-sided and multi-layer boards when necessary.