Design and Surface Finish of Coil Boards
1 min
Circular coils are a wiring method sometimes used in PCB layout. They serve primarily as inductors, transformers, antennas, and more. Considering the production of PCBs containing coiled traces, please take note of the following points:
1. Compared to conventional circuits, it might not be possible to detect short circuits between windings of circular coils if the coil is a closed circuit. Therefore, the requirement for trace width and spacing is 0.254 mm (with a limit of 0.15 mm, but only when the coil is covered with soldermask).
2. For exposed copper in the coil, only ENIG process is recommended (which offers relative flatness and a tighter thickness tolerance).
3. It is not advisable to use the hot air solder leveling (HASL) process for coils with exposed copper (HASL has large thickness tolerance and is prone to solder bridging between coil windings).
4. Coils covered with soldermask can be processed with either hot air solder leveling (HASL) or ENIG.
Keep Learning
Why Copper Oxidation Matters in PCB Design & How to Prevent It
Key Takeaways Copper oxidation is a critical concern in PCB design that directly impacts solderability, contact resistance, and long-term reliability. By understanding how oxidation forms and damages copper surfaces, designers can effectively prevent it through appropriate surface finishes (such as HASL, ENIG, and OSP), strategic solder mask application, and strict adherence to proper storage and handling practices per IPC-1601 guidelines. Protecting copper from oxidation ensures better assembly yield......
Solder Mask Colors: Boost Your PCB Performance, Style & Reliability
Key Takeaways Solder mask color directly impacts AOI accuracy, thermal performance, and PCB reliability — it is not purely cosmetic. Green remains the industry benchmark for the highest manufacturing yields and fastest turnaround at no extra cost. White maximizes light reflection for LED applications, while black offers a premium aesthetic for high-end consumer products. Red and yellow provide superior visual contrast for prototyping, debugging, and safety-critical inspections. JLCPCB offers all seven......
Comparing OSP Plating with Other PCB Surface Finishes
Key Takeaways OSP stands out as a cost-effective, ultra-flat, and environmentally friendly PCB surface finish with excellent solderability for fine-pitch components, making it ideal for high-volume consumer electronics. However, its short shelf life (3–6 months), sensitivity to handling and oxidation, and limited multi-reflow durability require careful storage and process control. When compared to HASL, ENIG, Immersion Silver, and Immersion Tin, OSP offers superior planarity and lower cost but trades ......
Hard Gold PCB Finish: Achieving Exceptional Wear Resistance and Contact Performance
Surface finishes are not all the same thing, and this is obvious beyond mention when you are dealing with parts that are beaten against one another over and over. Hard gold. The most common finish used when PCBs must complete hundreds or even thousands of insert-and-remove operations before going out of service is essentially a hard alloy of gold electroplated over a nickel barrier coating. The prototypical piece of evidence that demonstrates why this is important is the edge connector, otherwise know......
Copper Coin PCB : A Solution for Heat Dissipation
In the fast-evolving electronics industry, devices are becoming smaller, faster, and more powerful, while also coming in a compact size. Power is no longer a problem, but packing the device into a smaller form factor presents a serious challenge. Whether we are working on a power converter, LED lighting module, automotive ECU, or 5G communication device, the excessive heat reduces performance. It shortens the component lifespan. This is where Copper Coin-Embedded PCBs become a smart, modern solution f......
PCBs Gold Fingers - Why It Matters ?
What is PCB Gold Finger? PCB gold fingers refer to the metal contact points on a printed circuit board, typically located at the board's edge. They are commonly made of metallic materials such as gold or upgraded gold alloys . Since the surface of the pads is gold-plated and the conductive contacts are arranged like fingers, they are called "gold fingers". Gold is extremely resistant to oxidation and has strong conductivity in comparison with other PCB surface finishes like HASL. Although it looks nic......