Assembled printed circuit boards or PCBAs are an integral part of most digital and electromechanical devices and machines. There are various types of PCBs depending on materials used, application specifications, layers, design, components, and more. The demand for small devices with multiple functionalities has increased in recent years. This has driven the need for dense and compact PCBs. HDI PCBs are a solution to meet such dense designs with multiple components arranged on a small-sized board along with dense wiring. High Density Interconnect or HDI PCBs are more compact PCBs with denser wiring, smaller vias, and copper traces than most other conventional types of boards. This post discusses the distinguishing factors of HDI PCBs, their benefits, and more.

Differentiating Factors of HDI PCBs

Here we compare HDI PCBs with conventional boards. These are some distinguishing factors of HDI boards compared to traditional ones.

  • Compared to regular boards, the issues related to stray capacitance and signal attenuation are close to zero in HDI boards. This is mainly because of microvia technology which is not used in regular boards. The signal length in normal boards also may be more depending on the board size.
  • In HDI, direct holes are drilled through laser unlike through-holes in standard boards.
  • The compatibility issues in terms of pin counts and pitch packages are much lesser in HDI boards than normal boards.
  • Normal boards don’t serve the purpose when it comes to some mission critical applications in defense and aerospace sectors. HDI PCBs along with high speed components are drivers of digital advancements in aircraft which facilitate precise control over the aircraft without too many adjustments.

Benefits of HDI PCBs

Portability and miniaturization are two important factors when considering devices for personal and professional use. Working on your laptop or smartphone when traveling, remotely accessing the integrated system at your manufacturing unit via your smartphone, and so on have gained traction over the last few years. These requirements have triggered the need for HDI PCBs. HDI PCBs offer many benefits, especially for specific applications. Here are some of them.

  • On an average there are around 150 pins per square inch on an HDI board, and these versatile boards offer multiple routing options regardless of dense wiring.
  • This has been a major driving factor for microvia technology. In HDI boards, there are blind vias, microvias, and buried vias which enable dense circuitry and multiple components on a compact-sized board.
  • While the components may be placed close to each other, the signal needs to travel a small path in HDI PCBs compared to traditional boards. The components can be safely placed close because of the via-in-pads and blind vias used.
  • The varied types of vias including stacked vias offer an additional layer of protection to the wires and components as well as joints from external parameters and environmental fluctuations.
  • HDI boards offer an enhanced signal quality as most signal paths are short.
  • The number of layers on HDI boards for a particular number of components is lesser than the same requirement for normal board. For instance, if 8 layers are required for a normal board for a given requirement, HDI boards would suffice the requirement with only six layers. This also makes it lightweight and cost effective as the number of layers reduce.
  • HDI PCBs find applications in crucial sectors such as defense, medical, and aerospace aside from electronics and telecommunication and more.

If you are an OEM manufacturing: electrical, electromechanical, or digital compact sized products with advanced functionalities, you may require HDI PCBs for precision and accurate functioning. It is crucial to find an experienced PCBA service provider and share your exact requirements with them to get the right output. Suntronic Inc. has several years of experience in PCB manufacturing and offers HDI PCBs based on your requirements.