A double-sided PCB, also known as a dual-layer PCB, incorporates an additional layer of conductive copper compared to a single-sided PCB. This additional layer enables the designer to implement circuitry on both sides of the PCB, allowing for increased circuit density. Electronic components can be soldered to both the top and bottom layers of the PCB.
Double sided PCB offers a practical circuit design solution as they provide higher circuit density than single layer PCB while being more cost-effective and easier to manufacture compared to multilayer PCB. They are widely utilized in various electronic applications.
How to Make a Double Sided Circuit Board
- Choose a suitable PCB layout design tool based on your level of expertise and requirements. The schematic design is usually the starting point for the design.
- Print the finalized layout on high-quality glossy paper using a printer.
- Cut the substrate to the desired shape, ensuring it matches the dimensions of the PCB layout.
- Transfer the printed layout onto the substrate by using a heat transfer method with an iron. Apply firm pressure for about 20-30 seconds to ensure proper transfer.
- Use a scrubber or an appropriate cleaning tool to remove any excess laser ink from the PCB tracks, ensuring the tracks are clean and well-defined.
- Drill the necessary component holes on the substrate using a drill press, ensuring accuracy and proper alignment.
- Repeat steps 4 and 5 to transfer and clean the bottom layout onto the substrate.
- Immerse the printed substrate into a copper chloride solution for the etching process. The etching time typically ranges from 20-30 minutes, during which the exposed copper layer is gradually etched away.
- Use conductive ink or a fine-tip conductive pen to make the drilled holes conductive or apply a plating process to enhance conductivity.
- Apply a solder mask to both sides of the board to protect the traces, pads, and provide electrical insulation.
- Finally, place the required components in their designated locations and solder the circuit board, completing the manufacturing process of the double-sided PCBA board.
Why Use Double Sided PCB
The cost of a PCB is influenced by the complexity of its manufacturing process, and the number of layers is a key factor that impacts the design and manufacturing complexity. Opting for a 2-layer PCB can bring several benefits in electronics, as summarized by TechSparks:
- Flexibility: Certain applications require specific materials to meet environmental requirements, such as ceramics or Rogers materials for high-frequency applications, or metals for high-temperature environments. However, constructing multilayer boards with these materials can be challenging. On the other hand, 2-layer PCBs can be manufactured using a wide range of materials.
- Size reduction: By adding additional conductive layers, the circuit density can be increased. This allows for the placement of components on both sides of the PCB, enabling the use of smaller board sizes in electronic devices.
- Cost-effectiveness: PCB production may involve failures, and the cost of these failures can add up. However, manufacturers have extensive experience in producing double layer circuit board, resulting in lower failure rates and reduced costs compared to more complex designs.
- Wide range of applications: Advanced electronic applications often require higher circuit densities. While double layer PCB offer moderate circuit densities, they can be suitable for both advanced and simpler projects.
- Multi-functionality: In some circuits, it may be necessary for the PCB to absorb or provide current, or interact with other devices for current transfer or shielding purposes. In such cases, a double sided PCB board can be beneficial. The bottom layer of the board can be used as a ground source, providing effective grounding and ground references.
Examples of Applications for Double-Sided PCB Board
- Power Converter
- Control Relay
- HVAC System
- LED Lighting System
- Industrial Control Instruments
- Unmanned Vending Machine
- Power Amplifier
- Traffic Flow Control System
- Computer Motherboard
- 3D Printer
- Airbag System
- Electronic Stabilizer
- Portable Communication Device
- Network Camera