Master HDI Design: Expert Tips for High-Density Electronics

Dec 06,2019

High-density interconnect (HDI) continues to be the fastest growing segment in the PCB manufacturing as it makes the boards more efficient, whilst also allowing for faster transmission. Compared to the conventional PCB boards, HDI PCBs have a higher wiring density per unit area and are characterized by finer spaces and lines, minor vias, and capture pads, and higher connection pad densities. These PCBs are designed differently compared to conventional PCBs majorly in the way interconnections are made. In HDI PCBs, interconnections are made through blind holes and buried holes instead of through holes, as in the case of conventional PCBs. Likewise, there are many design tips that can optimize HDI design in electronics. Let’s have a look at a few amongst them that not only optimize HDI design but also helps to avoid expensive pitfalls.

Design Tips to Enhance HDI Design

HDI design allows for securing more components on both sides of the PCBs, which is not exactly possible with a standard PCB assembly. The success of any HDI PCB assembly lies in the manner in which the component space is arranged on the board and the way the designer distributes space for signal lines. The following design tips can also be kept in mind to guarantee high performing HDI PCBs.

• Via Type Selection:

  The selection of via type greatly determines the overall performance of HDI boards. Keep a note that the use of microvias, blind or buried, can reduce the complexity of the manufacturing process by reducing the number of layers and minimizing the material costs.

• Choose Components Wisely:

  When it comes to the assembly of HDI boards, the selection of components that go into the board must be done with utmost vigilance. Consider the trace widths, locations, types and sizes for drill holes and stackup before selecting components for your HDI design. Using the components wisely not only helps to optimize HDI design but also minimize the additional fabrication time and material costs.

• Stack:

  HDI PCB layer stack-up can be designed in several ways as 1-HDI (with buried holes), non-stacked 2-HDI (with buried holes), stacked but non resin filled 2-HDI, stacked and resin filled 2-HDI, and so on. Designers must pick up the most appropriate stack design to avoid one-side warpage and enhance the board yield.

• Space Components Wisely:

  Inappropriate component placement results in the introduction of electromagnetic interference (EMI) into traces, parasitic capacitances and/or inductances, which affect signal quality and overall performance. Space components in such a way to minimize stress and EMI, whilst also enabling easy assembly, PCB repair & rework services and soldering.   

Besides the aforementioned, the HDI PCB designers must also take care of the following design tips:

• Route traces in such a way to minimize signal integrity issues
• Maintain the right aperture ratio
• Incorporate microvias with an incredibly small diameter
• Place small components close to one another
• Distribute buried and blind holes in such a way to ease pressure
• Use buried planar capacitance rather than decoupling capacitors

HDI PCBs, which are largely chosen for enhancing the electrical performance of devices, find immense applications across industries. A few amongst the devices that get benefited from these PCBs include computers, smartphones, and medical equipment and so on. However, to design, assemble and optimize HDI Design, a manufacturer requires CAD and CAM software, laser direct imaging processes, special fabrication equipment, and operator expertise. The manufacturer experiences and capabilities greatly determine the success of HDI PCBs design. Therefore it is critical to associate with manufactures like Creative Hi-Tech who has a vast expertise in assembling unique, performance driven, and cost-effective HDI PCBs in par with your requirements. Creative H-tech boasts a team of knowledgeable, experienced, talented professionals who are well-versed with varied design tips to optimize HDI design in electronics.