High Density Interconnect (HDI) Printed Circuit Boards

High Density Interconnect (HDI) Printed Circuit Boards

High density interconnect (HDI) printed circuit boards allow more components to be placed in smaller areas than traditional PCBs. This increases functionality and reduces size, weight and cost, making them a more viable alternative to traditional boards for advanced technology systems such as smartphones and games consoles. In addition, HDI PCBs are increasingly being used in medical devices such as miniature sized cameras to assist doctors in patient diagnosis.

With a high number of interconnections in a smaller space, HDI PCBs require less raw materials and fewer layers than traditional PCBs. This leads to lower manufacturing costs and can allow you to produce a product at a price point that's more competitive than traditional solutions.

The design process of an hdi pcb requires careful consideration to ensure that signal integrity is maintained. This includes using the shortest possible trace lengths, designing consistent impedance paths between layers and ensuring that digital, analog and power signals are isolated. The choice of materials is also crucial. FR4, metal or fiberglass are common choices for core materials, while surface finishes include HASL, immersion tin, immersion silver and gold. The choice of laminate material and the number of sequential laminations also have an impact on the manufacturing cost of your board.

For HDI PCBs, laser micro vias are used to create connections between pads and internal layers, unlike the mechanical drilling processes used on non-HDI, standard PCBs. This is known as the "via in pad" process. The use of this technique allows for a higher pin count in BGAs, which can add significant cost savings and increase the density of your circuit board.

In order to accommodate the higher pin counts, HDI PCBs use a unique plating process called copper in-pad (CPIP). This is similar to the via-in-pad process used on standard PCBs, except that it's done through a laser instead of manually drilling and hand soldering. The ability to CCIP an entire component leads to significantly reduced assembly time and increased reliability.

The amount of sequential laminations used to fabricate an hdi pcb is a significant factor in its final cost. The number of sequential laminations required depends on the number of layers, the number of blind and buried vias and the complexity of the stack-up.

When selecting a PCB manufacturer, you should choose a partner with experience producing complex HDI boards and the necessary fabrication capabilities. You should also consider the turnaround time and customer service. Choosing a partner with the right experience and equipment will help you to avoid costly mistakes and achieve better results.

Once you have completed your hdi pcb layout and passed a DFM review, it's time to prepare the fabrication files for your manufacturer. The unified design environment in Altium Designer(r) gives you everything you need to create Gerbers and a Bill of Materials. The software can also create assembly drawings and the required CAD files for your bare board. Start your free trial of Altium Designer today to see what this powerful software can do for you.