Issue link: https://iconnect007.uberflip.com/i/1014812
30 DESIGN007 MAGAZINE I AUGUST 2018 at a higher cost, let's focus on those capabili- ties that allow us to work smarter. As an IC packaging EDA engineer, I argue that work- ing collaboratively with the system design and packaging engineers is one way we can enable denser designs that are completed faster, while still meeting signal integrity and power integ- rity requirements. Doing so requires more pre-planning and pre-analysis of the design, specifically looking at breakout patterns from the high pin-count devices, the critical signal typologies and routing schemes, and an up- front analysis of the critical signals within the design. Due to the complexity of designs and increased time pressures, the PCB designer may reap significant rewards by spending time planning the PCB design within the context of the components that will be mounted on the board. Spending more time on the initial plan- ning and partitioning of the design intercon- nect could allow the PCB designer to keep the number of layers low and meet the intended form factor and cost targets. How is this pos- sible? Cross-Domain Planning The PCB designer's ability to not only work within their own domain, but also extend their influence into the domain of the pack- age designer, allows them to enlarge the avail- able solution space. In many cases, large BGA footprints are no longer fixed entities but foot- prints that can be modified and optimized to assist the PCB designer in the completion of the task, as shown in Figure 1. Where possible, the PCB designer should have a mechanism to plan and optimize the entire system at a high level of abstraction before parts are placed on the board. Where there are large BGA footprints that are not fixed and still under design, they must have the abil- Figure 1: Board-driven ball map optimization.