editor's blog
Subscribe to EE Journal Daily Newsletter

Speeding up FLASH

Most of what you hear about FLASH developments relates to capacity. But bandwidth is becoming more critical as we stream more data around – particularly for applications where FLASH is replacing a hard drive. Yes, FLASH is already faster than a disk, but moving to solid-state storage – especially in growing data-intensive areas like cloud computing – will ramp up expectations on how much we can shove down that poor memory’s throat. Digital fois gras anyone?

At least this is how Cadence sees things happening (well, except for the fois gras part). They’ve just announced support for the higher-speed ONFi 3 interface standard, which revs up access to 400 MT/s –  twice what it used to be. In theory, anyway.

However, they also claim that most implementations of ONFi 3 only achieve 85-90% or so of that theoretical performance. Cadence claims that with their IP portfolio (PHY, controller, ECC), they can achieve 95% of that 400 MT/s.

They’re also touting their ECC – it’s becoming much more important at high densities for both probabilistic and sensing sensitivity reasons. This is especially true with cells that can carry more than one bit’s worth of information: you’re measuring fine gradations of trapped charge, increasing the risk of statistical errors.

Which brings me to my kvetch of the day… terminology. SLC = single-level cell. Your standard, garden-variety memory cell – on or off. One level; one bit; two values. Then there was multi-level cell, or MLC. As far as I was concerned, this was a generic term for anything more than one. “Multi” being rather, well, generic. But no – apparently in this language “multi” means two. Well, actually, that’s not even right. The number of levels in an MLC cell, by this definition, is 4 – there are 4 levels, equivalent to 2 bits’ worth of information.

And then there’s the confusing TLC – three- (or triple-) level cell. Which is doubly confusing since “three” should qualify as part of “multi” since it’s more than one. But it’s worse than that, since a TLC doesn’t have 3 levels – it has 8 levels, 3 bits’ worth of information. Call it a TBC perhaps. Or an ELC. Or an 8LC. TLC is just wrong. And defining “multi” as 2 (or 4) is just goofy.

OK, rant over. More info on Cadence’s announcement is available on their release

Leave a Reply

featured blogs
Sep 24, 2017
Recently, Renesas combined the Cadence® Interconnect Workbench, the Cadence vManager™ Metric-Driven Signoff Platform, and the Cadence Palladium® Z1 Enterprise Emulation Platform to improve their performance validation flow. They were looking for a better way to...
Sep 21, 2017
Everyone likes to browse the web a little bit differently. Some of us love images, while others are happy to browse text-based webpages all day long. This is why we’ve built a variety of different tools on Samtec.com over the years to assist you with finding the product...
Sep 01, 2017
Achronix was delighted to attend the Hot Chips event in Cupertino once again this August. This year saw a bumper turnout, with some very fascinating speakers providing some great insights into the industry. The Achronix team had a chance to meet with many talented people in t...