editor's blog
Subscribe Now

Go Wide

Last week Cadence announced a new wide-I/O memory controller IP block, ostensibly the first of its kind. This actually represents a risk start based on a JEDEC standard that’s not yet complete.

The idea behind the wide-I/O movement is predicated on use in 3D ICs, where a memory chip will be stacked on a logic chip, with the connections being made by TSVs. Instead of requiring higher-drive I/Os that connect to chip pads and traverse PCB traces to get to a memory chip (or back from the memory chip), you stay entirely within the package. An array of TSVs mean that you can handle far more I/Os that if you have to go to package pins. And the drive requirements are reduced tremendously, reducing both the size (due to smaller transistors) and power of the resulting combination.

Of course, with more connections, you get much higher bandwidth: this is a 512-bit interface. That’s a lot more data available in one chunk than you can traditionally get.

Cadence’s controller block includes traffic shaping algorithms to increase throughput as well as features to address power, including traffic sensing (so that power can respond to traffic) and an option for dynamic voltage and frequency scaling (DVFS).

This would seem to come well ahead of the standard, which is projected (no promises!) to be available to non-members in September. But, in many such standardization cases, the technical details are approved first, and then the resulting standard goes through a higher-level board approval step that largely examines the process by which the standard was set to make sure that it was done properly. 

Clearly Cadence is betting that there will be no further technical changes. Or that, if there are, they can update the IP before any customer commits to final silicon.

Leave a Reply

featured blogs
Apr 19, 2019
As platforms become more electrical, and the safety of flying becomes paramount, the FAA'€™s EWIS regulations serve as a cornerstone to modern aircraft wiring compliance and safety certification. EWIS (rhymes with '€œGee whiz'€) is both a concept and practice that embr...
Apr 19, 2019
Spring is here and we just got done with our first round of the cleaning action at home over the weekend. Yes, it usually takes us a few weekends to get to the "it-looks-great" feeling! In... [[ Click on the title to access the full blog on the Cadence Community si...
Apr 18, 2019
Thermal Shock testing isn’t unique to the connector world, but it does play a big role in the qualification testing that Samtec puts all connectors through before they are released for production. Chances are likely that you thermally shock many items per day and don...
Jan 25, 2019
Let'€™s face it: We'€™re addicted to SRAM. It'€™s big, it'€™s power-hungry, but it'€™s fast. And no matter how much we complain about it, we still use it. Because we don'€™t have anything better in the mainstream yet. We'€™ve looked at attempts to improve conven...