HDI Overview Video

Every generation of silicon demands more from your layout. As BGA pitch shrinks to 0.5, 0.4, and even 0.35mm, the available routing space is defined by microvia structures, fabrication limits, signal integrity, and thermal behavior all at once. This is an overview of how Allegro X approaches HDI design as a unified flow, from stack-up definition through constraint-driven routing and in-design analysis, without the back-and-forth between disconnected tools that typically drives up iteration count on complex boards. The HDI flow in Allegro X starts in the cross-section editor, where stack-ups are defined against fabrication constraints and drive everything downstream, impedance targets, routing rules, and via definitions for blind, buried, and via-in-pad structures. Microvias are defined through the pad stack editor, and the blind and buried via editor handles stacked and staggered microvia configurations across layers. All of those rules, spacing, via structures, pad rules, live in a unified constraint manager that enforces them in real time as you route, so DFM violations surface during layout rather than after. For BGA fanout, constraint-driven routing manages breakout channels, layer transitions, and via selection within the bounds of your electrical and fabrication rules simultaneously. And because Allegro X integrates directly with Sigrity X solvers, signal integrity, return path behavior, and power integrity can be validated inside the layout environment rather than exported to a separate simulation workflow for signoff. The result is an HDI design flow where stack-up definition, routing, analysis, and manufacturing verification happen in one place which on a dense AI accelerator or high-speed interconnect board is the difference between one revision and three.