The dramatic growth hoped for in the mobile device industry can only happen if the creativity of both device designers and
applications developers can be freed from oppressive demands of outdated architectures that are based on attempts to further miniaturize already overly complex systems or to retrofit power-hungry PC architectures to a pocket-sized, untethered, 24/7 world.
The answer is to be able to offer smartphones, feature phones and a wide variety of converged and mobile devices at mass-market prices. To do this, Freescale has taken a major step in the design of the core architectures used to power such devices.
Limitations of existing architecturesThe early-generation analog cellphones consisted of a discrete single CISC-based microcontroller (MCU) core controlling a number of analog circuits. The move from analog to digital technology drove the need for a digital signal processor (DSP) core to be added to the architecture. Dual-core architectures, consisting of an MCU and a DSP, evolved from several discrete parts to a single ASIC in the mid ’90s.
Current dual-core baseband architectures were not designed to support the feature requirements of converged devices, and as a result, today’s smartphone architecture requires additional processing resources by adding a discrete application processor to the discrete dual-core cellular baseband IC. Each processor requires its own memory system comprising RAM and Flash.
Support for additional wireless networking, such as Wi-Fi and Bluetooth wireless technology, requires additional modules for each function, including radio transceivers, digital basebands, RAM and Flash components within the module. This approach yields a system architecture having a minimum of three, or as many as six, CPUs, each with its own dedicated memory system, peripherals, clock generator, reset circuit, interrupt controller, debug support and interprocessor communications software.
Rethinking architecture designAdoption of features, such as color display, cameras and converged capabilities, would not be possible without advances in semiconductor technology, microarchitectures and embedded systems. It is for this reason, and to implement more advanced features such as 2-D and 3-D graphics, mobile multimedia, Mobile IP and personal entertainment, that Freescale has created the Mobile eXtreme Convergence (MXC) architecture.
Freescale Semiconductor, with its more than 50 years of technology know-how, has with the MXC architecture initiated the first major rethinking of wireless and mobile smart handheld architecture, reducing complexity, size and power consumption.
The size of a postage stamp, the MXC is capable of changing almost any product into a smart, cellular-enabled device. Because
the architecture is small, powerful and scalable it could, for example, turn clothing, headsets, or devices such as cameras and MP3 players, into fully functional smart mobile cellular devices.
Freescale’s MXC architecture offers seamless access to multimode features, such as world connectivity, Internet readiness, wireless local-area networking (WLAN), global positioning service (GPS) and Bluetooth connectivity, coupled with the ability to deliver portable applications, such as multimedia messaging, voice activation features, gaming, wireless photos, mobile video and MP3 playback and many other consumer applications that the mass consumer market has yet to enjoy because of complexity, high costs and unwieldy size created by current architectures.
The MXC platform is the result of 24 months of intense research and development by a team of Freescale engineers. Freescale India Design Centre at Noida has been involved in the development of MXC architecture since 2004. The Indian team played a key role in the baseband, design specification and validation for MXC technology.
Design approachKey architecture changes include:
• The convergence of all protocol processing into a single core, which drives the entire range of global cellular and local
connectivity protocols, eliminating as many as six processor cores and dropping part count and complexity.
• An integrated applications processing function, which allows developers to write once and port their applications to any other device, using a consistent processing core.
• Shared memory systems and reduced interprocessor communication systems to free up processing capability, reduce part count and streamline communication.
• Hardware acceleration and memory caching techniques to cut power consumption.
When productized, the architecture will deliver a complete smartphone platform in a 16 20mm package and a slim 1.4mm, enabling virtually any device—an MP3 player, a handheld DVD player, a digital camera—to become a smartphone.
Driving down costsMXC is a single core modem, with strict separation between modem and applications. It also has integrated multimedia, graphics and security support. This approach protects the critical communications functions from “open” applications and enables orthogonal development efforts thereby cutting cycle times. When implemented, this platform could eliminate the need for standalone applications processors in cellular phones thus reducing cost and development time.
The MXC architecture completely rethinks how a phone platform is designed, providing a 50 percent reduction in design complexity. It is the first single architecture for manufacturers and applications developers to cost effectively bring applications into the mass-market at favorable price and cost points.
The MXC architecture unites digital signal processing, applications processing and multiple connectivity systems—
functions previously performed by many dozens of memory-and power-hungry components into one highly integrated nucleus.
This simpler approach removes layers of architectural redundancy, creating lower overheads, lower memory requirements, fewer handoffs and opportunities to drop instructions, as well as lower development and manufacturing costs.
This architecture eliminates the need for standalone application processors in mobile devices and reduces the number of components on board to less than 100 from the existing 170 to 200. This would, therefore, provide an impetus to the low-cost handset market.
Freescale’s architects envisioned MXC architecture during a period when many processor architects were employing heterogeneous architectures. The company (then operating under the Motorola flag) took a daring step in the opposite direction with MXC.
Today, the MXC family of processors unifies baseband, control, and applications on one die. Major achievements in this architecture are the integration of these functions on one chip employing fewer cores with resulting smaller die size and price. External power consumption has been reduced by removing communications among separate chips and by fewer accesses to
external memory.
In view of these achievements, the Microprocessor Report from the Reed Electronics Group voted to award Freescale’s MXC91321,
(from the MXC family of chips) as the MPR Analysts’ Choice Award for Best Applications Processor for 2005.
This recognition reiterates the capabilities and potential of this architecture to drive mobile commerce, and enrich the mobile experience of the mass-market consumer through easy-to-use, compact and affordable universal mobile products.
A mobile consumer’s life requires the support of products based on a technology that delivers marathon battery life, peace-ofmind security, access to instant entertainment, anywhere-to anything connectivity, and industrial designs that deliver optimal usability for the application.
No power struggleThe MXC architecture is just that—it combines smart integration driven by decades of wireless know-how with a clean application environment. There’s no power struggle—both worlds function ideally. It converges Smart Speed performance with stamina technology with good security technology. It allows manufacturers to converge this postage stampsized smart phone core with product designs and applications tailored to millions of market segments.
MXC is currently sampling with Freescale’s customers. In May 2005, Freescale announced the first GSM voice call on a true single core modem with the MXC platform, a collaborative effort with Motorola. Motorola has also made the first WCDMA and GSM voice calls on the Freescale MXC platform. This new, very small, single core modem will drive interesting applications in the mobile device market and users could very well see the first generation MXC-powered devices launched in 2007, heralding a new era in wireless devices.
Author informationYou can reach Ganesh Guruswamy at
PRIndia@freescale.com
