Is America Ready for Qseven?
The U.S. may follow Europe’s lead for the design of ultra-mobile applications.By Christian Eder, congatec AG
A lot of the growth in the electronics industry can be attributed to the consumers’ love affair with devices that continuously become smaller and more portable. Key technologies are emerging to support the mobile and ultra-mobile trend, such the Intel® Atom™ processor. Yet many of the enabling components that are needed to leverage these new capabilities have hit a wall.
Take computer-on-modules (COMs), for example. Existing specifications like COM Express, XTX, and ETX have exhausted their potential when it comes to developing the lowest-power-consuming and mobile applications. When COM Express was defined back in 2001, central-processing-unit (CPU) power consumption was quite different. Today’s mobile CPU and chipset combinations are now below 5 W. This dramatic change in chip technology clearly demands a new approach when it comes to COMs.
In 2008, three European companies collaborated to develop a new, open standard to enable smaller-sized, lower-power applications based on an embedded-module concept. Called Qseven, the standard was defined for next-generation, ultra-mobile embedded processors that were built using 45-nm and below technologies. Unlike previous COM standards, Qseven was specifically intended for low-power applications that could handle the rigorous requirements of mobile and ultra-mobile applications.
Since its inception less than two years ago, this specification has gained wide use in Europe. More than two dozen companies are already actively working with the published specification. Initial products designed with Qseven are expected to hit the market within the next few months. Despite the overwhelming support abroad, however, U.S. companies are under-represented in this effort. Currently, the Qseven Consortium has just one U.S. member.
For American designers to remain competitive, it’s time that they recognize and understand the benefits of this standard. With the rapid momentum that it has already achieved in enabling stateof- the-art product design, it’s clear that this standard is here to stay. For further proof, look at the breadth of members that are committed to supporting it and the cost savings that it can provide. These benefits are detailed in the following paragraphs:
Enables state-of-the-art technology - Chip manufacturers have brought several new technologies to the market that couldn’t have been foreseen when legacy standards like ETX, COM Express, and XTX were first defined. New interfaces also have been developed. In addition, computing performance has increased dramatically while energy consumption has decreased dramatically. While COM Express permits a maximum power consumption of 188 W, for example, contemporary processors like the Intel Atom consume ~2 W. In addition, Qseven was designed from the ground up to be legacy-free with a specific focus on mobile and battery-operated applications. Lastly, its interfaces are compatible with state-of-the-art chipsets. (See Figure 1.)
Figure 1: This edge finger pinout diagram illustrates Qseven interface connections.
Long-term viability - Supporters of Qseven include a wide range of companies ensuring the long-term availability and support of Qseven. The most recent member is FoxConn Technology Group. As one of the four largest MXM connector providers worldwide, its membership guarantees longevity and further enhancements for the Qseven connector. A minimum of eight companies (see listing at www.Qseven-standard.org) already offer their own Qseven computer- module designs.
Cost savings - When development teams at system and device manufacturers discuss ways to reduce development time and cost, they usually end up turning to the use of COMs. Module-based solutions can be highly flexible when it comes to configuring to the needs of dedicated applications. With just a single-carrier-board design, it’s possible to create an entire product family merely by varying the computing power of the modules. The ability to react to new processor and chipset technologies can also be ensured simply by exchanging modules.
Because the modular concepts are standardized, it’s easy to change the module vendor and thus reap the benefit of multiple sources. From the hardware view, this is true for all COM definitions. Most COM modules are equipped with additional functions for industrial applications. Examples include the watchdog timer, I²C bus, LCD brightness control, BIOS user storage area, and the reading of system temperatures. Due to the fact that no standardized software interface for these functions has yet been defined, the theoretical exchangeability of COMs has in practice proven to be more difficult than expected. To generally avoid the software modifications that such situations would require, the Qseven specification includes a consistent software application programming interface (API). Qseven modules from different manufacturers can thus be easily exchanged without modifying the hardware or software.
Qseven At A Glance
The name Qseven is derived from the word “quadratic,” which is represented by the Q, and seven, which refers to the 7-x-7-cm² size of the module. Unlike most previous module standards, Qseven doesn’t require an expensive board-to-board connector. Instead, it utilizes the small and rugged but very affordable MXM connector with 230 pins in a 0.5-mm configuration. Despite its small size, the module’s construction is very robust (with a 1.2-mm-thick printed-circuit board). This MXM slot connector is produced by four manufacturers in two different heights. In addition, versions are available with 30-μm goldflashed contacts for industrial applications. (See Figure 2.)
Figure 2: This top view shows a congatec Qseven design.
To support the feature set of current and future mobile CPU/ chipset combinations, Qseven only defines current interfaces. Older “legacy interfaces,” such as Parallel IDE and PCI bus, have been deliberately omitted to avoid the additional effort and associated costs of supporting them.
Qseven defines the following interfaces:
- 4x PCI Express x1 lanes
- 2x SATA
- 8x USB 2.0
- 1000BaseT Ethernet
- SDIO 8 bit
- LVDS 2 x 24 bit
- SDVO/HDMI/DisplayPort (shared)
- High Definition Audio (HDA)
- I²C bus
- Low Pin Count Bus (LPC)
- Fan control
- Battery management
- 5-V power (TDP max. 12 W)
- Application programming interface
Together, the four PCI Express lanes enable a data transfer rate of about 8 Gbits/s in each direction compared with up to 22 PCI Express lanes for COM Express. This may not seem like much. Yet such high I/O bandwidth is only required for server-side or highend graphics applications—not mobile devices. The Qseven concept is already prepared for the next-generation double-data-rate interfaces like PCI Express 2.0 and SATA II.
The video interfaces have been designed with increased flexibility. In addition to a digital video input, a total of four different output possibilities are defined. In parallel to the 2-x-24-bit LVDS interface for the direct control of flat-panel displays, one of the digital display interfaces—SDVO, TDMS, or DisplayPort—can be used independently. DisplayPort is one of the latest VESA definitions (www.vesa. org). Compared with DVI, TDMS, and LVDS, DisplayPort offers an extendable, packet-based protocol that can carry additional information, such as audio, in addition to pure display data.
The Qseven specification is freely available and may be used without any license fees. Membership in the Qseven Consortium is also free of charge. For more details, visit www.Qseven-standard.org.
Christian Eder has nearly 20 years of experience in technology. He began in product-management positions at Kontron GmbH and CPCI Systems (Force Computers) before joining startup JUMPtec AG as a marketing manager. After that, Eder was director of marketing at EMEA, Kontron AG. He is a co-founder of congatec AG and currently serves as the firm’s vice president of marketing. Eder received his degree in electrical engineering from the University of Applied Sciences, Regensburg, Germany.