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
Oct 18, 2018
Look around, look around at how lucky we are to be alive right now'€¦ '€”Lin-Manuel Miranda, Hamilton Every once in a while, I write a post like this one, to highlight some of the amazing things that are happening in the world of electronics and technology. Today I culled...
Oct 17, 2018
Samtec offers one of the industry'€™s largest and most flexible lines of two-piece, pin-and-socket board-stacking interconnects. To say it another way, we have more ways to stack two or more boards together than any other connector company.  Also, you can specify a cust...
Oct 16, 2018
  IC Insights has just published the September Update to The 2018 McClean Report, and one figure (reproduced below) puts yet another nail into the coffin for poor old Moore'€™s Law. Now please take care. There'€™s a vertical line between the 200mm wafers on the left ...
Oct 12, 2018
At the end of the day, your products are only as good as their in-the-field performance. It doesn'€™t matter how well they performed in a controlled environment....