SemiSerious

On March 20, the famous Gibson Guitar Corporation sued Harmonix, MTV, and EA for infringement of US Patent 5,990,405 – System and Method for generating and controlling a Simulated Musical Concert Experience. The defendants named are meant to cover the entire Guitar Hero series as well as the newer Rock Band game. Gibson has since expanded its suit to cover various retailers who sell the games including Wal-Mart.

Gibson Guitar Corporation’s complaint, filed in the Nashville Division of Tennessee District Court (courtesy of Wired’s Game|Life) specifies the alleged infringement like this:

THE INFRINGING PRODUCTS AT ISSUE
16. Defendants have and continue to manufacture and/or sell products that infringe, contribute to the infringement of and/or induce the infringement of at least claims 1, 13-15, 25 and 28 of the ‘405 Patent and/or have no other substantial noninfringing uses.

Considering how the music industry works today, you have to assume that Harmonix spent a lot of time and legal fee dollars working out licensing deals with record labels for the songs that appear in Guitar Hero. After all that work, it’s no surprise that they may have overlooked the possibility of a company outside the gaming world developing the concept first.

But that’s not all. According to SI device sourcing guru, Allan Yogasingam, ActiVision has already paid a license fee to Gibson for use of the signature Les Paul style of guitar for its game controller. The Les Paul image and brand is a lot more valuable (and stronger) than the patent cited in this case.

Before reading the complaint above, I read through the claims of the ‘405 patent trying to determine what angle Gibson’s lawyers were taking. There are four independent claims and 26 supporting claims. At least one independent claim needs to be map to the game system for Gibson to have a case.

Claim 13 is the broadest, but will it hold up to prior art scrutiny? How do karaoke machines fit in? Wikipedia suggests that the first machine was invented in Japan in the 1970’s. The entry for Karaoke history points out that the original inventor did not patent the machine. The Philippines granted a Letters Patent (UM-5269) in 1983 to its most famous inventor, Roberto del Rosario, for a system originally prototyped in 1975.

But one key element of ‘405 in all the claims is the use of a video interface as well. Although the earliest karaoke machines relied on singers to know the words or read them from a paper song sheet, video teleprompting entered the fray some time in the eighties. I may not be young and hip and part of today’s crowd of gamers, but I wasn’t quite hitting the karaoke bars back then. Perhaps one of my blogging elders could help me sort out more accurate dates for the introduction of video into the karaoke system. The ‘405 patent was filed in 1998 years after video technology was readily available to the karaoke set.

Claim 21 maps most directly to the game. It specifies a guitar. That is the focal point. Gibson’s lawyers arguments against the prior art hinge on the definition of “musical instrument.” It won’t be the first time a huge bill gets rung up over semantics, but this case will come down to whether singing into a microphone constitutes a musical instrument or not. Your favorite singer won’t get a vote.
 

For years, there has been speculation that traditional SRAM would be replaced with a denser type of memory for SoC devices. In fact, TI once announced that they would use ferroelectric RAM or FeRAM beginning at 90nm for their devices. Fear of ever-worsening process variability has been widespread. Alas, we have entered the 45nm period, and SRAM continues to be the workhorse of the industry.

I’m not suggesting there has been no competition. Once upon a time, it was popular to use a DRAM cell, hide the refresh inside a circuit macro, and call it 1T-SRAM.

But why have these alternatives either never been used (FeRAM and others), lost favor (as it seems in the case of 1T-SRAM and eFlash), or been relegated to only very high density, very high speed applications (as with DRAM)? But don’t expect an answer, I’m just posing these questions - at least for this week. Winter has weighed me down too much to think about such things.

DRAM has enjoyed some success, so let’s take a closer look. The bits are denser. A DRAM cell occupies only eight times the minimum area unit of a given process technology versus about 120 or more for an SRAM cell. Looking at it this way, SoC DRAM should be a no-brainer right? Wrong. The DRAM is dynamic RAM. That is, leakage in the cell access transistor will erase the contents of the cell. So the cell has to be refreshed. The circuit overhead for cell refresh along with some other operations means that the DRAM taken as a complete circuit macro will only be smaller than an SRAM for densities beyond about 4MB.

Until very recently, SoC DRAM has been narrowly confined to graphics processors from gaming consoles. Microsoft, Nintendo, and Sony game systems have all used graphics engines that integrated large embedded DRAM (eDRAM) arrays onto their chips. The semico’s that actually produced the chips were ATi/NEC, IBM, and Sony/Toshiba. IBM has enjoyed a long history in the development of DRAM and embedded DRAM. IBM invented trench capacitor DRAM, and this type has become the de-facto standard for SoC devices. I say that despite NEC’s stacked capacitor structure used in one of the XBOX 360 chips. In fact, the ATi/NEC chip is a very special case of eDRAM. It’s really more of a DRAM with integrated memory controller. Dick James has some interesting thoughts on eDRAM in game consoles that you can reach with this link.

The Sony gaming consoles are an interesting case study. Consider this. PS2 and PS3 consoles contained graphics engines with eDRAM. However, the hand-held PSP does not. Instead, a commodity DRAM die is packaged, SiP style, along with a pure logic LSI device. You might say that portable devices need to be more energy efficient and would demand the use of single-chip solutions over multiple die which typically suck more power. But there is more price and manufacturing cost pressure on the PSP driving Sony’s choice for the portable platform. High development and process integration costs are certainly limiting the use of eDRAM. I think the lesson from Sony is actually more general and addresses the whole SoC versus SiP debate.

My take is that eDRAM will only ever exist in a couple of places. It will continue to provide extremely large on-chip arrays for memory-hungry special purpose graphics processors. It will also become more common where bits need to be neatly packed along the columns of an LCD driver. But once again, this will only be for extremely memory intensive applications such as mobile drivers with very large color depth.

Other than that, SRAM will reign supreme. For the best example, look at the Qualcomm MSM7500 die micrograph at the top of this post. For a complicated SoC architecture like this, embedding DRAM makes no sense. Another example of SRAM maintaining its foothold is the latest 45nm MPU. Since Intel still did not integrate a memory controller onto the Penryn, the design still relies on a huge 6MB L2 cache, but it’s still good, old-fashioned SRAM.

The Sony Playstation 3 finally arrived on store shelves in select corners of the globe this week. Sony’s complex third generation gaming console has experienced multiple delays - shipping at least a year later than hoped by Sony execs and gaming fans everywhere. After much anticipation, we finally received the Sony Playstation 3 and got to have look inside.

The Playstation 3 is Sony’s entry into the next generation of gaming consoles. Sony claims that this is the most powerful gaming system around, and has additional features that move it beyond just gaming, like the BlueRay player.

The semiconductor world has looked forward to the launch of the Cell MPU as a significant milestone in computer design for the masses. The Cell device was to be designed from the very beginning with 65nm process technology in mind. But alas, this is all hindsight. Sony had to opt for the Cell device in 90nm technology just to avoid being even further behind the year lead of the Microsoft XBox360 and soon to be released Nintendo Wii.

Stay tuned as we examine the Playstation 3 and the devices inside that make it tick.