Printed Circuit Board (PCB) minimum annular ring refers to the minimum amount of copper between the edge of the land and the edge of the hole, after the finished hole is plated. It is also referred to as a supported hole. Sometimes, the traces on a circuit board are required to be connected to another layer. In such cases, the traces end up on a pad. The via on the pad helps the trace to move from that pad and connect the other layer. The area on the pad, which surrounds the via is referred to as annular ring. It is very crucial to have a proper setting of the annular ring in the PCB layout software. This helps maintain proper spacing of copper. Twisted Traces is a company, which can help you in setting a proper annular ring for your printed circuit board.
Calculating the Annular Ring
The copper ring, which is also referred to as the annular ring, makes a through-hole pad around a drilled hole. For the purpose of creating via, the drilled hole is surrounded by the ring of copper. In case of vias, this is most commonly referred to as outer diameter or via size. According to the IPC-2221A standard, the PCB minimum annular ring size is calculated as follows:
Minimum Annular Ring = (Min Ring Border)*2 + (Hole Size) + (Tolerance)
|Minimum Annular Ring on the Inner Layer||0.1mm|
|Minimum Annular Ring on the Outer Layer||0.05mm|