Double Sided PCB
Double Sided PCB add an extra layer, allowing greater capacity for components. They’re ideal for high-performance applications that push the limit on functionality and electrical performance.
The second layer offers flexibility for layouts, allowing for critical signals to be closer together. This allows for more reliable circuits, enabling robust prototyping blueprints to come to life sooner.
Design
Double-sided PCBs are often used for higher-tech applications such as cell phones and car dashboards. This is because they allow for a greater number of circuits to be placed in the same physical space, thereby improving component density and signal integrity. They can also support higher voltages and digital circuit speeds than single-sided boards.
The design of a double-sided PCB starts with the creation of a schematic diagram. Once this is complete, the layout of the components and copper pathways on both sides of the board can be drawn using various PCB design software. The final layout must be verified to ensure the correct functionality and that there are no issues with the design before it is sent for fabrication.
During the manufacturing process, the two layers of copper on both sides of the board are etched to remove any excess material. Then, the top and bottom circuits are plated with a layer of solder mask. This layer is typically a shade of green and acts as the “veil” that protects the components during reflow soldering.
Preparing a double-sided PCB for manufacture requires the same tools that are used to design a multilayer Printed Circuit Board (PCB). These include PCB layout tools, layer stackup managers and the ability to generate Gerber files and Bill of Materials to streamline production. Your tool should also have error-checking features that can compare your layout to a standard set of design rules.
Layout
In Double Sided PCBs, the components and conductive copper are mounted on both sides of the board. The two layers are separated by a dielectric layer and a solder mask. The top side is printed with a copper layer and the bottom side is covered by a green shaded layer known as the solder veil. The conductive copper of the top and bottom layers is connected through holes known as vias.
Using a double-sided PCB allows Double Sided PCB more circuit space and complexity than a single-sided PCB. It also allows you to place incompatible signals like analog further apart from digital signals, which reduces crosstalk and improves performance. In addition, a double-sided PCB is cheaper than a multilayer board because it requires less material.
The first step in the process of creating a double-sided PCB is to draw the schematic diagram. Various circuit board design software is available online that can help you do this. Once the schematic is complete, it’s time to start the layout process.
The layout of a Double Sided PCB is relatively straightforward if you use a high-quality tool. However, it is essential to make sure that the traces do not overlap with each other. This can cause the solder to dribble and weaken the circuit’s connections. It’s also important to avoid 90 degree bends on the traces. This can create a loop and short out the circuit.
Drilling
Double-sided PCBs have a layer of conductive copper on both sides, enabling them to support components on both sides. The circuits on each side are connected to each other via drilled holes, known as vias. They can be connected using either through-hole technology, where leaded components are installed into pre-drilled holes and soldered to them, or surface mount technology, where the leads of the component are inserted into pads on the board itself.
For the first step, you will need to select a suitable substrate material. FR-1 is a good choice for double-sided PCBs as it is copper clad on both sides and has a thin sheet of phenolic resin in the middle to hold the two sides together. Next, you will need to run a DFM check on the design and correct any flaws found in the traces, holes, or component placements.
After you have finished the design, it is time to mill out the top of the PCB. Make sure to use a dremel tool with a 0.4 mm bit to get the best results. To avoid any misalignment, be sure to align the PCB with the alignment bracket when you mill it.
Once you’ve completed the milling of the top side, you can start on the bottom. To do this, you’ll need to mirror the gerber files for the bottom side and then create an Excellon Object (drill job) and a CNC Job Object just like you did in the previous steps.
Testing
In PCB fabrication, there are two main types of printed circuit boards: single-sided and double-sided. Single-sided PCBs have components mounted on one side of the board, while double-sided ones have conductive wiring on both sides. Double-sided PCBs offer several advantages over single-sided PCBs, including lower cost and greater design flexibility.
During the designing stage of a double-sided PCB, it is important to capture accurate schematics and layouts. This ensures that the circuits are properly connected and will function as intended. It also helps prevent errors that may occur during the production process, such as missed connections or incorrect component placement. Capturing schematics with proper software can help reduce the number of errors and save time.
Once the circuit patterns are captured, the board is immersed in an etching solution. This removes the photoresist layer and exposes the copper layers, which are then etched to create the desired PCB supplier circuit pathways. This step is crucial for achieving a high-quality double-sided PCB because it ensures that the pathways are clear and ready for automated optical inspection.
When installing components on a double-sided PCB, it’s essential to follow precise guidelines to avoid mistakes and damage. Start with large and heavy pieces, such as transformers or heat sinks, then install smaller items like resistors and capacitors. Once all the surface-mounted pieces are secure, install the through-hole components, making sure they’re positioned correctly and have enough clearance.
