Single-Sided PCBs: Dead or Just Sleeping?

A single-sided PCB can look old beside modern multilayer boards, yet that does not make it useless. I still see it serving a clear purpose in products that need a low-cost circuit, a short production cycle, and a layout that is easy to inspect.

The real question is not whether single-sided PCBs are outdated. The better question is whether the board matches the product.

What a single-sided PCB is

A single-sided PCB has copper traces on one side of the board. Components are usually placed on the other side, though some designs use surface-mounted parts on the copper side as well. Electrical connections pass through drilled holes, solder joints, or short wire links.

The structure is easy to understand:

• One copper layer
• A base material such as FR-4, paper phenolic, or another suitable laminate
• Drilled holes for through-hole components
• Solder mask and component markings when required

This layout gives designers less routing space than a double-sided or multilayer PCB. It also keeps the manufacturing process relatively direct.

When I review a product design, I do not treat fewer layers as a weakness by itself. A board with fewer layers can be easier to repair, easier to inspect, and easier for a small production run to manage.

Where single-sided PCBs still work well

Single-sided PCBs fit products with low circuit density and limited routing needs.

Common examples include:

• LED lighting controllers
• Basic power supplies
• Small audio devices
• Simple timers
• Toys and educational kits
• Household switches
• Alarm units
• Low-complexity control panels
• Some battery-powered devices
• Basic industrial signal boards

A simple LED sign is a useful example. If the circuit only connects a power input, resistors, LEDs, and a control component, the design may not need multiple copper layers. Using a multilayer board could add cost without giving the product a clear benefit.

I have also seen single-sided boards used in small control products where repair staff need to follow each trace by eye. The visible path can make fault finding more direct, especially when the board has large components and wide tracks.

The board can also work well for products with a long service life and stable circuit requirements. A fixed-function device may not need the routing space offered by a modern high-density PCB.

Why some companies still choose this design

The main appeal comes from production control and design simplicity.

A single-sided PCB may offer:

• A lower material requirement
• A shorter routing path for basic circuits
• Easier visual inspection
• Fewer hidden trace problems
• Convenient through-hole assembly
• A practical option for small batches
• Straightforward repair work

The actual price depends on board size, material, copper weight, hole count, surface finish, order volume, and manufacturing location. A single-sided design is not automatically the cheapest option in every case.

For instance, a board with many wire jumpers may require extra assembly work. If production staff must install and solder several links by hand, the saving from using one copper layer can become smaller. I always compare the board cost with assembly time before recommending this route.

The limits of single-sided PCBs

The main problem is routing space.

When many traces must cross each other, a one-layer board cannot solve the layout by adding another copper path. The designer may need to use:

• Wire jumpers
• Larger board dimensions
• Wider trace spacing
• More component movement
• Different component packages
• A change to the circuit layout

These choices can affect the product enclosure and production process.

Signal quality can also become harder to manage. A single-sided PCB has limited options for ground planes, power distribution, shielding, and controlled impedance. High-speed digital circuits, radio modules, sensitive analog circuits, and dense microcontroller systems often need more routing control.

Heat management may create another concern. If a power component produces heat, the available copper area can be limited. The designer needs to check trace width, copper thickness, thermal paths, and airflow before selecting the board structure.

A single-sided PCB may also need more physical space. The board can become larger when the circuit has many connections. A double-sided design may reduce the footprint even if its unit price is higher.

Single-sided PCB or double-sided PCB?

I compare the two designs through the product requirements rather than through age or appearance.

A single-sided PCB may suit the project when:

• The circuit has few connection paths
• The operating frequency is low
• The board can use through-hole parts
• The enclosure allows more space
• The product has limited functions
• Repair access matters
• Production volume supports the chosen process
• The design does not need a large ground plane

A double-sided PCB may be more suitable when:

• The board must stay small
• The circuit contains many crossing traces
• The product uses dense surface-mounted components
• Grounding needs more control
• The design includes faster signals
• The board includes several connectors or modules
• Manual jumpers would slow assembly
• Thermal or power distribution needs more copper area

Multilayer boards become useful when the product needs dense routing, stable power delivery, signal separation, or controlled impedance. A compact router, medical monitor, industrial controller, or modern computing product may need this structure.

The right choice depends on the circuit, not the number of layers alone.

How I decide whether a single-sided PCB is suitable

I use a basic review process before accepting the design direction.

Check the schematic

I count the main components, connectors, power paths, and signal groups. A schematic with many independent blocks may create routing pressure even when each block looks simple.

Estimate routing density

I place the largest components first and draw the critical connections. If traces cross often, I test whether a few wire links can solve the issue without creating assembly problems.

Review power and heat

Power traces need enough width for the expected current. Heat-producing parts need a suitable copper area and a reasonable distance from heat-sensitive components.

Check the product size

A single-sided PCB can work well when the enclosure has spare room. If the product must fit into a thin or compact case, a double-sided design may reduce the board area.

Review assembly work

I ask how the board will be assembled. A design that looks inexpensive at the PCB factory may take more time on the production line if workers must install many jumpers or hand-solder parts.

Think about service needs

For products repaired by local technicians, visible traces and large through-hole parts can be helpful. For sealed products made in high volume, automated assembly and board size may carry more weight.

Test the first prototype

A prototype can reveal issues that do not appear in a schematic review. I check electrical performance, temperature, mechanical fit, soldering quality, and repair access before placing a larger order.

A practical example

Imagine a small 12-volt LED controller with a switch, resistors, a timer chip, and a few indicator lights. The circuit operates at a modest speed, uses common components, and fits inside a plastic enclosure with enough room for a 100 mm board.

A single-sided PCB could be a reasonable choice. The traces are easy to arrange, the current paths can be made wide enough, and the components are easy to replace.

Now imagine a compact wireless controller with a microcontroller, radio module, USB interface, battery charger, sensors, and several high-speed signal lines. A single-sided layout may require many jumpers and a larger board. It may also make grounding and signal control harder. A double-sided or multilayer PCB would give the designer more useful routing options.

Both products use a PCB. Their needs are different.

Common design mistakes

One mistake is choosing a single-sided board only because the initial board quote looks lower. Assembly labor, wire links, inspection, testing, and rework can change the total cost.

Another mistake is forcing a complex circuit onto one layer to avoid changing the design. This can produce narrow traces, crowded components, weak ground connections, and difficult repairs.

Some teams also ignore future changes. A board that works for the first version may become difficult to update when the product gains a sensor, connector, display, or communication function.

I prefer to leave a reasonable amount of routing space and test points. A small increase in board area can make production and repair easier.

Single-sided PCBs are not outdated by default. They remain useful for low-density circuits, basic controls, simple power products, educational devices, and designs where clear inspection matters.

They become a poor fit when the circuit needs compact routing, strong grounding, high-speed signal control, or heavy component density.

My view is practical: choose the fewest layers that support the electrical, mechanical, thermal, and production needs of the product. A single-sided PCB can be the right engineering choice when its limits are understood and planned for.

When I choose a PCB for a product, I do not always start with a multilayer or double-sided board. Many designs only need one copper layer. In these cases, a single-sided PCB can offer a clear path from prototype to production without adding extra structure, cost, or assembly work.

The key is matching the board type to the product. A single-sided PCB will not fit every circuit. It works best when the design has a moderate number of components, simple routing, and limited signal demands.

A single-sided PCB has copper traces on one side of the board. Components are usually mounted on the opposite side, although some designs use through-hole parts placed directly on the copper side. Since the circuit uses one conductive layer, the layout needs careful planning.

I often see single-sided boards in products such as:

• LED lighting units
• Simple power supplies
• Battery chargers
• Timers and control panels
• Home appliance controls
• Audio accessories
• Small industrial devices
• Automotive signal modules with simple circuits

A basic LED driver is a practical example. The circuit may contain a few resistors, capacitors, a connector, and a control component. If the traces can be routed on one side without many crossings, a single-sided PCB may meet the electrical and production needs.

The board structure also helps control manufacturing cost. A simpler design usually requires fewer process steps than a board with several copper layers, plated vias, and tighter alignment requirements. The actual price still depends on board size, material, quantity, surface finish, drilling, testing, and supplier capacity. I never treat “single-sided” as a promise of a fixed price.

There is another benefit that is easy to miss: repair work can be more direct. When the traces are visible on one side, a technician can inspect the circuit with less disassembly. Fault tracing may take less time on a simple control board. This can help products that need field service or regular maintenance.

Material choice still matters. A common board may use FR-4, while some low-cost devices use paper-based materials such as FR-2. FR-4 offers better mechanical strength and heat performance for many applications, but the right material depends on operating temperature, moisture, mechanical stress, and safety needs.

The design process needs discipline because routing space is limited. I usually check the circuit in this order:

1. Define the electrical function
   I confirm voltage, current, frequency, connector positions, and component ratings before placing anything on the board.

2. Place the parts by function
   Components that work together should stay close. A power input section should not be separated from its protection parts. Sensitive signal paths should stay away from noisy switching areas when possible.

3. Plan trace paths
   I route the main power and ground paths with suitable width. A narrow trace may create unwanted heating or voltage drop when the current rises.

4. Reduce jumper use
   Single-sided boards may need wire jumpers to cross traces. A small number of jumpers can be practical, but too many can slow assembly and create more points for mistakes.

5. Check clearances
   The distance between traces, pads, and board edges should match the voltage level and manufacturing capability. High-voltage sections need special care.

6. Review heat and mechanical needs
   Components that generate heat need space and a suitable copper area. Mounting holes, switches, displays, and connectors should match the product housing.

7. Test a sample
   I check electrical performance, assembly fit, solder quality, and repair access before approving a larger batch.

A small control panel shows where this approach can work well. Imagine a timer used in a household device. It may contain a microcontroller, a few buttons, a display connector, and a power section. If the signal count is limited and the layout is planned around the controller, a single-sided design may be workable. If the same product later adds wireless communication, high-speed data, or many interface lines, the board may need more layers.

That trade-off should be discussed early. A single-sided PCB can reduce design complexity, but it can also limit routing freedom. Long traces may increase noise. Wire jumpers may make automated assembly less convenient. Dense circuits may require a double-sided or multilayer board to keep the layout safe and reliable.

I see the best results when the PCB choice follows the circuit rather than a cost target alone. Saving money on the board does not help if the design creates assembly problems, signal interference, or repeated repairs.

Single-sided PCBs still matter because many products do not need a complex board structure. They can support practical circuits, visible trace inspection, simple repairs, and cost-aware production when the design fits their limits. My approach is simple: define the circuit needs, plan the layout with care, test the board, and choose a more complex PCB only when the product truly requires it.

Are single-sided PCBs making a comeback?

I see this question often when engineers compare low-cost circuit boards with newer multilayer designs. The answer is not a simple yes or no. Single-sided PCBs never fully disappeared. They remain useful when a product has a simple circuit, limited routing needs, and strong cost pressure.

Many design teams now look at single-sided boards again because material use, production steps, and inspection can be easier to control. A simple board may not need four or six layers. Choosing more layers than the circuit needs can raise the board cost without improving the product.

I usually start with the circuit, not the board type. The right question is: can the design meet its electrical, mechanical, and safety needs with copper on one side?

A single-sided PCB has conductive traces on one side of the board. Components are normally mounted on the opposite side or placed through holes that connect to the copper pattern. The structure is easy to understand, which can help during repair and production.

Products that may use this structure include:

• LED lighting units
• Simple power supplies
• Household control panels
• Toys and basic consumer devices
• Timers and alarm circuits
• Small fans and motor controls
• Some low-density industrial equipment

A simple LED driver is a useful example. The circuit may contain a few resistors, capacitors, a connector, and a control component. If the traces can be routed without crossing each other, a single-sided PCB may meet the design need.

The cost benefit comes from more than the copper layer count. A basic board can require fewer manufacturing steps and may be easier to test. Drilling, soldering, and component placement still affect the total price, so a single-sided design does not guarantee a low-cost product. The complete design must be reviewed.

I pay close attention to routing before making a decision. Single-sided boards have limited space for traces. When two signal paths need to cross, the designer may need a jumper wire, a different component position, or a revised circuit layout. Each extra workaround can affect assembly time and product appearance.

A practical review can follow these steps:

1. List the circuit functions and signal paths.

2. Mark power, ground, control, and high-current traces.

3. Place large components and connectors.

4. Route the most sensitive or high-current paths.

5. Check whether the remaining traces can stay on one copper side.

6. Review clearances, heat, soldering access, and mechanical fit.

7. Compare the full production cost with a two-sided design.

Signal quality needs attention as well. A simple control circuit may work without a large ground plane. A high-speed communication circuit may need better return paths and tighter control of noise. A single-sided board can be suitable for low-speed electronics, but it may create extra design work for circuits with fast edges, radio signals, or dense connections.

Heat is another point that is easy to miss. Copper areas can help spread heat, but a single-sided board offers less routing freedom for thermal design. Components that carry power need suitable trace width, copper thickness, spacing, and airflow. The design should be checked under normal operating conditions rather than judged only from the schematic.

Manufacturing limits also shape the decision. A factory may have clear requirements for trace width, spacing, hole size, solder mask, and component placement. A board that looks simple on a screen may still be difficult to assemble if parts are crowded or jumpers are placed near solder joints.

I have seen simple boards become more expensive after too many manual fixes were added. A jumper wire may solve one routing problem, but ten jumpers can create extra labor and inspection points. At that stage, a two-sided board may offer better value, even if its base price is higher.

Repair needs can support a single-sided design. Technicians can often follow the copper paths with less effort, and damaged traces may be easier to locate. This can help equipment used in workshops, basic control systems, and products that need field service.

Product life also matters. A stable design with modest performance needs may stay on the market for many years. A simple board structure can make sourcing easier when the manufacturer already has suitable materials and assembly equipment. The design still needs a supply review, since component availability can change even when the PCB structure stays the same.

A single-sided PCB is not a return to an older method. It is a useful choice for a defined set of products. It works best when the circuit is not dense, signal speeds are moderate, heat is manageable, and the factory can build the board with limited manual work.

My view is simple: layer count should follow circuit needs. A single-sided board can reduce cost and make service easier, but it can also create routing limits and assembly issues. A two-sided or multilayer board may be the better fit when the layout is crowded, the signals are sensitive, or the product needs stronger thermal control.

The most reliable decision comes from comparing the whole product, not only the PCB quotation. Review routing, testing, assembly, repair, electrical performance, and long-term sourcing together. That process shows whether a single-sided PCB is a practical choice or only a low-price option that creates extra work later.

When I design a small electronic product, I often look for the simplest circuit board that can meet the electrical and mechanical needs. A single-sided PCB can be a practical choice for products with basic layouts, low component density, and controlled routing requirements.

It has copper traces on one side of the board. Components are usually mounted on the opposite side or placed on the copper side, depending on the assembly method. This structure reduces the number of manufacturing steps and can help control the board cost.

The key is knowing when the design is suitable.

What a single-sided PCB can handle

I usually consider a single-sided board for circuits such as:

• LED lighting controls
• Simple power supply boards
• Basic alarm devices
• Small audio circuits
• Relay and switch control boards
• Sensor modules with limited connections
• Consumer products with low circuit density
• Educational electronics projects

A simple LED controller is a useful example. If the circuit contains a few resistors, a small control chip, connectors, and LED outputs, the traces may fit on one copper layer. The board can be easy to inspect and suitable for repeated production.

A board with many fine-pitch components, several power rails, or a high-speed signal path may need two or more copper layers. Choosing a single-sided structure for a dense circuit can create routing problems and increase manual wiring or jumper use.

Why many designers choose this board type

Cost control is one reason. A single-sided PCB often uses less copper and fewer processing steps than a multilayer board. The actual price still depends on board size, material, thickness, surface finish, hole count, order volume, and production requirements.

The layout can also be easier to review. I can trace a signal path on one copper layer without checking several internal layers. This helps during early testing and repair.

Production can be more straightforward for basic products. Fewer layers may reduce some alignment and lamination requirements. The final result still depends on the factory process, design files, inspection method, and assembly quality.

Repair work may be easier as well. Technicians can see most of the conductive paths from one side, which helps when checking an open circuit, damaged trace, or incorrect connection.

Limits to consider before design

A single copper layer provides less routing space. When several traces need to cross, I may need to change the component position, use a jumper wire, or redesign part of the circuit.

Power and ground paths need careful planning. A narrow or long trace can add resistance and produce voltage drop. High-current areas should use suitable trace width, copper thickness, and connection points based on the expected load.

High-speed signals need extra attention. Long traces, sharp corners, poor grounding, and nearby interference sources can affect signal quality. A single-sided board may not provide the same ground structure as a multilayer design.

Thermal management also matters. A small copper area may not remove heat effectively from a power transistor, regulator, resistor, or LED. I check the component datasheet and allow enough copper area for the expected operating condition.

A practical design process

I start with the circuit diagram and list the parts that need special treatment. Connectors, switches, transformers, heat-producing parts, and large capacitors affect the available space, so I place them before smaller components.

The next step is arranging the main signal flow. I keep related components close together and shorten sensitive connections. Power input, protection parts, regulation stages, and output connections should have a clear path.

I then route the copper traces on one layer. When two traces need to cross, I look for a layout change before adding a jumper. A small position adjustment may remove the crossing and make assembly easier.

Trace width should match the current level. Low-current signal traces can be narrow within the manufacturer’s design limits. Power paths may need more width or a larger copper area. I also check the spacing between traces based on the working voltage and production capability.

The design rule check should cover:

• Minimum trace width
• Minimum spacing
• Hole diameter
• Annular ring size
• Board edge clearance
• Component clearance
• Solder mask openings
• Copper area connections
• Polarity marks and reference labels

I review the board from the assembly point of view before releasing the files. A connector that is too close to the board edge can cause trouble during installation. A diode or capacitor without a clear polarity mark can slow down production and testing.

Example from a simple control board

Suppose I am designing a board for a small cabinet light. The circuit includes a DC input connector, a fuse, a switch, a resistor, an LED driver, and several LED outputs.

The input protection parts should stay near the power connector. The LED driver should sit near the output connections. The control signal should be kept away from noisy power paths when the layout allows it.

This board may fit well on a single-sided PCB if the number of outputs is limited. I can use a wider copper path for the supply and return lines, keep the LED channels organized, and place clear labels beside each connector.

If the same product later adds wireless communication, display control, several sensors, and a compact enclosure, the routing needs may change. A two-layer board could offer better flexibility and a cleaner ground connection.

Choosing materials and finishes

FR-4 is a common material for many general electronic products. Its suitability depends on temperature, mechanical requirements, thickness, and operating conditions.

Board thickness affects strength and installation space. A thin board may fit a compact enclosure, while a thicker board may provide more mechanical support.

Surface finish affects soldering and storage performance. The right choice depends on the assembly process, component type, expected storage conditions, and production volume. I confirm these details with the PCB supplier before placing an order.

The board should also match the intended soldering method. Through-hole assembly, hand soldering, and surface-mount assembly may require different pad layouts and component clearances.

How I avoid common mistakes

I do not treat a single-sided PCB as a universal solution. I compare the circuit size, current, voltage, signal speed, heat, and assembly method before choosing the layer count.

I avoid placing too many components close to the edge. I keep test points accessible and label connectors in a way that helps the person who will assemble or service the product.

I also check the manufacturing files carefully. The Gerber files, drill file, component drawing, bill of materials, and assembly instructions should describe the same design version. A mismatch between these files can delay production or lead to incorrect assembly.

A prototype gives useful feedback. I can use it to check fit, signal behavior, soldering access, connector position, and heat during normal operation. A prototype does not replace product testing, but it can reveal layout problems before a larger production run.

Single-sided PCBs work well when the circuit is compact, the routing is manageable, and the electrical demands are moderate. They can support cost-conscious product development without adding unnecessary board complexity.

My usual approach is simple: define the circuit limits, plan the component placement, route the power paths with care, check the manufacturing rules, and test a sample before production. When the design no longer fits those conditions, moving to a two-layer or multilayer PCB may be the more practical choice.

When people talk about the future of printed circuit boards, they often focus on multilayer designs, high-speed signals, and compact electronic products. Single-sided PCBs receive less attention, yet they still serve many products where low cost, simple routing, and easy assembly matter.

I see single-sided PCBs remaining useful in areas where the circuit does not need dense wiring or advanced signal control. Their future will not depend on replacing complex boards. It will depend on matching the board structure to the product.

A single-sided PCB has conductive traces on one side of the board. Components are usually mounted on the opposite side or placed on the same side as the copper pattern, based on the assembly method. This structure creates clear limits, but it also keeps production simple.

A simple design can reduce several common problems:

• Lower material use
• Easier inspection
• Shorter production steps
• Fewer drilling and routing needs
• Simple repair work
• Lower entry cost for basic electronic products

I often see these boards used in LED lighting, toys, small household appliances, battery-powered devices, control panels, and basic power circuits.

A single-sided PCB may not suit a compact device with many components. It can still be a practical choice when the circuit has a limited number of connections.

Why single-sided PCBs still have a place

Many buyers want a board that meets the circuit requirement without adding extra layers. A multilayer board can support more routing space, but it also requires more design work, material control, and production checks.

For a simple LED controller, a single-sided board may provide enough space for resistors, connectors, switches, and control parts. Using a more complex board structure could add cost without improving the product.

I once reviewed a basic lighting project that used a two-layer board during the early design stage. The circuit had only a small group of components, but the layout was spread across both sides. After the design team changed the routing plan, the circuit fit on a single-sided board. The product still needed safety checks, but the board structure became easier to understand and assemble.

This type of decision depends on the circuit, product size, operating voltage, heat level, and assembly method. The cheapest board is not always the right board. The suitable board is the one that meets the product needs with fewer unnecessary steps.

Design limits need early attention

Single-sided PCB design requires careful planning because every trace must share one copper layer. Crossed routes cannot pass through each other in the same way they can on a double-sided board.

I pay close attention to these points during layout planning:

1. Component placement

Large parts should be positioned before small components. Connectors, switches, transformers, and heat-producing parts can affect the rest of the layout.

1. Trace direction

I arrange traces in clear paths and leave space for difficult connections. A crowded layout can lead to jumpers, longer traces, or design changes during production.

1. Electrical clearance

The space between traces should match the working voltage and the board material. Power circuits need more care than low-voltage control circuits.

1. Heat control

A single-sided PCB may need wider copper traces, heat areas, or extra spacing around warm components. The board should be checked under the expected operating conditions.

1. Assembly method

The layout should match through-hole assembly, surface-mount assembly, or a mixed process. Component direction, solder access, and inspection space affect production quality.

These checks help prevent a common mistake: choosing a single-sided PCB only because it appears less expensive at the quotation stage.

Where the next demand may come from

The future of single-sided PCBs may be linked to products with simple functions and long production cycles.

LED products are one example. A basic lamp or sign may need a circuit for power control, current management, and connection points. If the layout remains simple, a single-sided board can be easier to produce in large batches.

Small appliances are another area. A fan controller, heating control panel, or simple timer may not need the routing space of a multilayer design. A single-sided board can make repair and visual inspection easier for service teams.

Educational kits and hobby products may also continue to use this structure. New users can understand a one-layer circuit more easily because the conductive paths are visible and direct.

Some industrial control accessories may use single-sided boards as well. A simple indicator panel or relay interface does not always need a complex layer stack. The choice depends on the required current, isolation, space, and product standards.

Materials and production choices

The board material affects reliability and cost. Common options include phenolic paper materials and glass-reinforced epoxy materials. The suitable choice depends on heat, strength, moisture exposure, and product use.

For a low-cost indoor product, a paper-based board may be suitable when the circuit and environment allow it. A glass-reinforced epoxy board may offer better mechanical strength for products that face more heat or physical stress.

Copper thickness also needs attention. A high-current path may require wider traces or thicker copper. Increasing copper thickness alone does not solve every heat problem. The trace width, board size, component temperature, and airflow should be reviewed together.

Surface finish affects soldering and storage. The finish should match the assembly process and the expected shelf period. A production team can recommend a suitable option after reviewing the components and manufacturing conditions.

Automation will affect simple board production

Single-sided PCBs may become easier to produce as factories improve inspection and assembly systems. Automated optical inspection can check trace shapes, solder areas, and missing parts. Automatic testing can help detect open circuits and incorrect connections.

These tools do not remove the need for good design. They help manufacturers identify problems with more consistent procedures.

Digital production data can also reduce errors between design, purchasing, and assembly teams. When the same board information is used across each step, teams can reduce manual changes and improve traceability.

Material use may receive more attention as manufacturers review waste, energy use, and product life. A smaller board with a simple layer structure may support a lower material load, but the full product design still needs to be assessed. Board size, yield, packaging, and service life all affect the result.

How I decide whether to use a single-sided PCB

I use a simple review process:

• List every component and connection.
• Mark power paths and heat-producing parts.
• Check whether the traces can be routed on one copper layer.
• Review the required board size.
• Confirm the assembly method.
• Compare prototype and production needs.
• Check safety spacing and testing requirements.
• Ask the manufacturer about material and process limits.

If the design needs many jumpers, unusual routing, or a large increase in board size, a double-sided PCB may be more suitable. If the circuit remains clear and stable on one layer, a single-sided PCB deserves serious consideration.

The decision should be based on the complete product cost, not only the board price. Assembly time, repair work, testing, material waste, and production yield can change the result.

Single-sided PCBs will not serve every future electronic product. High-speed communication devices, small wearable products, and dense control systems often need more routing space and stronger signal control.

Their role can remain steady in products that value simple structure, controlled cost, easy inspection, and practical manufacturing. I believe the future of single-sided PCBs will come from careful application rather than broad replacement. When designers understand the circuit limits and manufacturers support the process, a simple board can still provide a dependable path from concept to finished product.

Single-sided PCBs are often treated as an old choice, but that view misses their practical value. I still see them in products that need a simple circuit path, controlled cost, easy inspection, and steady production.

A single-sided PCB has copper tracks on only one side of the board. Components are usually placed on the other side, though some parts may be mounted on the copper side when the design allows it. The structure is simple, which can reduce manufacturing steps and make the board easier to review.

When I select a PCB structure, I do not start with the question, “Which board is more advanced?” I start with the circuit itself:

• How many connections are required?
• How much space is available?
• Will the board carry low current or higher power?
• Does the product need shielding, impedance control, or dense routing?
• Will the board be made in large batches?

For a simple circuit, a single-sided PCB may solve the job without adding unused layers.

A common example is a basic LED lighting controller. The circuit may contain a few resistors, a connector, a switch, and an LED driver. If the signal paths do not cross, a single copper layer can be enough. The same idea appears in some toy products, small power control boards, simple timers, alarms, and low-cost consumer devices.

TV remote controls also show why single-sided PCB designs remain useful. The circuit is usually compact but not highly dense. The board mainly connects buttons, an infrared LED, a small controller, and a battery supply. A simple layout can keep production and inspection straightforward.

Cost is one reason companies continue to consider this board type. A single-sided design normally uses less copper and fewer printed layers than a double-sided or multilayer board. The manufacturing flow can be easier to manage, especially when the circuit does not need plated through-holes for connections between layers.

This does not mean every single-sided PCB has the same price. Material choice, board size, copper thickness, surface finish, hole count, tolerance, order volume, and testing requirements still affect the quotation. A simple layer count does not remove the need for a full design review.

The main design limit is routing. With copper available on only one side, traces cannot freely cross each other. I often solve this by changing the component position, adjusting the circuit path, using jumpers, or selecting a double-sided board when the layout becomes crowded.

Jumpers can help, but they need space and assembly planning. A wire link or zero-ohm resistor may cross a trace, yet it also adds a component position, a production step, and another point for inspection. If the design needs many jumpers, the single-sided approach may no longer be the practical option.

Heat also needs attention. A single-sided board can carry power, but the copper area must match the current and thermal needs. Narrow traces may heat up under load. A designer should review trace width, copper thickness, component spacing, ventilation, and the material used for the board.

For power circuits, I usually check these points before approving a layout:

• Trace width for the expected current
• Clearance between high-voltage and low-voltage sections
• Distance around connectors and exposed contacts
• Heat produced by resistors, diodes, and switching parts
• Mounting holes and enclosure limits
• Soldering access during assembly
• Test points for production checks

The board material also changes the result. FR-4 is common because it offers stable mechanical performance and electrical insulation. Paper-based phenolic materials may suit some low-cost products with lower mechanical and thermal demands. The right choice depends on the product environment, not only the board price.

Single-sided PCBs can support both through-hole and selected surface-mount parts. Through-hole components are often easy to inspect and can work well for connectors, switches, transformers, and parts that receive mechanical stress. Surface-mount parts may save space, but the solder pad layout must leave enough room for assembly and repair.

I once reviewed a small controller design where the circuit was simple, but the board had many unnecessary crossings. The initial plan used a double-sided PCB. After moving the connector, rotating several resistors, and grouping the control section, the circuit fit on one copper layer with a small number of wire links. The change worked because the circuit did not require dense signal routing. If the board had included a fast data interface or many independent power paths, the same approach would have created more risk.

That is the key difference between a useful cost decision and a forced cost decision. A single-sided PCB should not be selected only because it appears cheaper. The layout, assembly time, repair method, and long-term supply plan all matter.

A practical review process can look like this:

1. Draw the circuit and mark power, signal, and ground paths.

2. Place connectors, switches, mounting holes, and parts with fixed positions.

3. Group related components so the traces do not travel across the full board.

4. Route the main paths and check whether crossings can be removed through placement changes.

5. Add jumpers only when they offer a clear production benefit.

6. Review trace width, spacing, holes, solder pads, and component height.

7. Ask the manufacturer to confirm material, copper thickness, surface finish, tolerances, and inspection methods.

8. Build a sample and test it under the actual voltage, current, temperature, and mechanical conditions.

This process helps expose problems before volume production. It also gives the manufacturer enough information to quote the board with fewer assumptions.

Single-sided PCBs are less suitable for dense communication circuits, compact computers, complex motor control, and designs that require controlled impedance. They may also be a poor fit when the enclosure leaves little room or when the board must carry many connections across a small area.

A double-sided PCB can solve some of these limits by providing another copper layer for routing. A multilayer PCB may be needed when the product requires high routing density, power planes, signal control, or strong separation between circuit sections. The right choice comes from the electrical and mechanical demands of the product.

I do not see single-sided PCBs as a design method waiting to disappear. They remain useful where the circuit is clear, the routing is manageable, and production simplicity has value. The board may look less complex, yet a well-planned simple board can be easier to manufacture, test, repair, and source.

The question is not whether single-sided PCBs are old or new. The better question is whether the circuit needs more than one copper layer. When the answer is no, a single-sided PCB can still be a sound engineering choice.

Want to learn more? Feel free to contact lingchao: mr.xu@lingchaopcb.com/WhatsApp +8613780181891.

IPC 2012 IPC-2221B Generic Standard on Printed Board Design

Ralph J Smith 2008 Printed Circuit Boards Design and Technology

Clyde F Coombs Jr and Happy T Holden 2008 Printed Circuits Handbook

Tim Williams 2014 The Circuit Designer’s Companion

Kraig Mitzner 2019 Complete PCB Design Using OrCAD Capture and PCB Editor

Erik O K Oras 2020 Practical Guide to Printed Circuit Board Design and Manufacturing