HDI PCBs, or High Density Interconnect PCBs, are circuit boards characterized by a high wiring density and small pad sizes. This technology allows for more connections within the same area compared to traditional PCBs. The use of microvias and blind/buried vias enables designers to create more compact and efficient layouts. HDI technology is particularly beneficial in applications requiring advanced performance and miniaturization.

HDI PCBs typically utilize multiple layers, allowing for complex circuitry in a reduced footprint. The layers can include various types of vias, which facilitate electrical connections between different layers of the board. This construction enables the integration of more components and functionalities, making HDI PCBs a preferred choice in many modern applications.