Subject: Processors | December 8, 2016 - 09:00 AM | Josh Walrath
Tagged: Xilinx, TSMC, standard cells, layout, FinFET, EDA, custom cell, arm, 7nm
Today ARM is announcing their partnership with Xilinx to deliver design solutions for their products on TSMC’s upcoming 7nm process node. ARM has previously partnered with Xilinx on other nodes including 28, 20, and 16nm. Their partnership extends into design considerations to improve the time to market of complex parts and to rapidly synthesize new designs for cutting edge process nodes.
Xilinx is licensing out the latest ARM Artisan Physical IP platform for TSMC’s 7nm. Artisan Physical IP is a set of tools to help rapidly roll out complex designs as compared to what previous generations of products faced. ARM has specialized libraries and tools to help implement these designs on a variety of processes and receive good results even on the shortest possible design times.
Design relies on two basic methodologies. There is custom cell and then standard cell designs. Custom cell design allows for a tremendous amount of flexibility in layout and electrical characteristics, but it requires a lot of man-hours to complete even the simplest logic. Custom cell designs typically draw less power and provide higher clockspeeds than standard cell design. Standard cells are like Legos in that the cells can be quickly laid out to create complex logic. Software called EDA (Electronic Design Automation) can quickly place and route these cells. GPUs lean heavily on standard cells and EDA software to get highly complex products out to market quickly.
These two basic methods have netted good results over the years, but during that time we have seen implementations of standard cells become more custom in how they behave. While not achieving full custom performance, we have seen semi-custom type endeavors achieve appreciable gains without requiring the man hours to achieve fully custom.
In this particular case ARM is achieving a solid performance in power and speed through automated design that improves upon standard cells, but without the downsides of a fully custom part. This provides positive power and speed benefits without the extra power draw of a traditional standard cell. ARM further improves upon this with the ARM Artisan Power Grid Architect (PGA) which simplifies the development of a complex power grid that services a large and complex chip.
We have seen these types of advancements in the GPU world that NVIDIA and AMD enjoy talking about. A better power grid allows the ASIC to perform at lower power envelopes due to less impedence. The GPU guys have also utilized High Density Libraries to pack in the transistors as tight as possible to utilize less space and increase spatial efficiency. A smaller chip, which requires less power is always a positive development over a larger chip of the same capabilities that requires more power. ARM looks to be doing their own version of these technologies and are applying them to TSMC’s upcoming 7nm FinFET process.
TSMC is not releasing this process to mass production until at least 2018. In 1H 2017 we will see some initial test and early production runs for a handful of partners. Full blown production of 7nm will be in 2018. Early runs and production are increasingly being used for companies working with low power devices. We can look back at 20/16/14 nm processes and see that they were initially used by designs that do not require a lot of power and will run at moderate clockspeeds. We have seen a shift in who uses these new processes with the introduction of sub-28nm process nodes. The complexity of the design, process steps, materials, and libraries have pushed the higher performance and power hungry parts to a secondary position as the foundries attempt to get these next generation nodes up to speed. It isn’t until after some many months of these low power parts are pushed through that we see adjustments and improvements in these next generation nodes to handle the higher power and clockspeed needs of products like desktop CPUs and GPUs.
ARM is certainly being much more aggressive in addressing next generation nodes and pushing their cutting edge products on them to allow for far more powerful mobile products that also exhibit improved battery life. This step with 7nm and Xilinx will provide a lot of data to ARM and its partners downstream when the time comes to implement new designs. Artisan will continue to evolve to allow partners to quickly and efficiently introduce new products on new nodes to the market at an accelerated rate as compared to years past.