The Cell Phone is Dying

Our own little world of mobile devices is changing rapidly. The thing we know today as a cell phone is morphing into a mobile media device that will be more closely aligned with a laptop than a cell phone by 2012. I was visiting a handset manufacturer recently and was talking about memory requirements for the future handset. Their requirement will be a minimum of 12GB/s by 2013/14. I asked why they needed such high bandwidth; what types of applications were they expecting to run on those devices? The person’s response was very simple. They are expecting to run anything a laptop runs today and then some. The consumer is already accustomed to being connected to their network of friends in real time. Their expectation is to have total application connectivity whenever they need/want it. Being able to carry the equivalent of a laptop in their pocked will be a requirement. I predict that the computer we carry from meeting to meeting, country to country, airplane to airplane today will stay home on our desks while the new mobile media device that, oh by the way, happens to make a phone call, will be what we rely to keep us productive while on the road, away from the office or away from home. I know there is the netbook craze mounting in the marketplace and it will certainly have its place. But we are already seeing the future of where cell phones are going with the wave of new Smartphones spurred on by the Apple iPhone. These devices will continue to become more complex and capable of executing media-rich applications like 1080p high-definition video.

The companies who make chips for these devices have to scramble to keep up with the requirements. A new class of high bandwidth memory chips is in the definition stage as I write this blog; employing an innovative serial interface capable of meeting the speed and low power demands of the future. Serial Port Memory Technology is the first such technology to get to the final specification stage. There are other technologies and techniques out there that are being investigated but right now, none really meet the requirement. Wide I/O TSV is the most talked about. Nokia and others have been pushing for further investigation to see if it will meet their power requirement. While it seems promising, other issues such as cost, manufacturability, potential reliability issues and scalability will most likely relegate it to a niche market at the ultra high end. It certainly won’t be a general purpose solution. Users already see the current LPDDR2 technology hitting the wall as far as bandwidth is concerned. So it pretty much leaves serial as the only viable way forward. The MIPI organization has been trying to push the MPHY as a serial DRAM interface solution. On the surface it seems to make sense. Having one PHY to populate the cell phone design including the DRAM is in the realm of nirvana. Only problem is that it won’t happen. Turns out, to make the MIPI MPHY work for DRAM you pretty much have to strip out most of the MPHY specification to the point where it is no longer a MPHY so you are back to at least two PHY technologies. Furthermore, the way the MIPI PHY technology is spec’d, all of the DRAM manufacturers are totally against it. It would be much too difficult and costly to implement. It was a nice thought, though.