Standards for aspect ratios and drill tolerances.
The standard is "generic" because it applies to all types of rigid and flexible PCBs, regardless of their end-use. It acts as the "umbrella" document for a series of more specific standards (such as IPC-2222 for rigid boards and IPC-2223 for flex boards). Ipc-2221 Pcb Design Pdf
IPC-2221, titled "Generic Standard on Printed Board Design," is the foundational industry document for creating reliable and manufacturable printed circuit boards (PCBs). It serves as a primary guide for electrical spacing, material selection, and conductor sizing across all types of organic printed boards, including single-sided, double-sided, and multilayer designs. Standards for aspect ratios and drill tolerances
Even with the open on a second monitor, engineers regularly make these three errors: IPC-2221, titled "Generic Standard on Printed Board Design,"
Compare IPC-2221A (current) with the draft of IPC-2221B. The proposed changes to via-in-pad plating ratios reveal where the industry is panicking (hint: buried vias for 5G).