One of the key questions facing designers of mobile consumer devices today is what functionality must the next-generation design offer? Whatever the exact configuration, mobile devices will clearly need to link seamlessly to home entertainment and office computing equipment in addition to serving as personal entertainment and communications devices. A configurable system solution based on programmable fabric will be essential in this rapidly evolving market so that developers can create designs that combine high-integration, high-performance, and low-power operation while keeping pace with changing requirements.

Many different interfaces will need to be incorporated into next-generation mobile devices for them to take on their expected role as central elements in consumer electronics. The functions that are converging in mobile device designs include portable media players, digital camera/camcorders, handheld video games, and enhanced mobile phones with web browsing and PDA capabilities. While all these applications are unlikely to fully converge, they will steadily integrate features from a shared “wish list.” That list includes functions such as coprocessors, high-capacity storage, WLAN and Bluetooth wireless interfaces, image capture, GPS and television tuners. Combining these features can be a difficult and risky design effort especially since the exact mix that the market will demand is difficult to predict.

Mobile devices present system architects with a nearly unsolvable dilemma. On the one hand they must offer customers a never-ending supply of features based on new standards, delivering high-performance at high-integration levels, and ensuring long battery life. Their designs will also have to be flexible so they can offer customization to achieve product differentiation as well as ease the development of successor products. On the other hand, system architects must adopt design approaches that reflect the market realities of short market windows and inevitable commoditization with ensuing price wars. The design approach they choose must offer a combination of high-performance, high-integration, and ease of design, flexibility and low-power.

Connectivity Solution Platform

Fortunately, there is a technology that achieves all of these goals: the connectivity solution platform, which combines programmable fabric with dedicated hardware that addresses a range of common system functions. These functional blocks may be dedicated to a specific function, or be configurable to take on one of several variations on a basic capability. By providing substantial functionality in pre-configured hardware, while also offering customization through programmable fabric, this connectivity solution platform simplifies design efforts by combining high-performance and integration with flexibility.

For next-generation mobile devices, one of the critical system capabilities that needs to be addressed is the processor’s ability to connect through a variety of popular interfaces. These include USB and SDIO for peripheral connections, UART to link with Bluetooth and GPS components, IDE and CE-ATA for mass storage, and SDHC and NAND Flash connections for local storage. In addition, the processor may need to drive an LCD display, provide video output, provide content protection and encryption and connect to digital television and networking chipsets.

Building all of these interfaces into a processor chip set in a one-size-fits-all approach however, is costly, time-consuming and risky. Not all interfaces will be required in any given product design, and the price premium paid for the unused capability would limit the chip set’s market. Further, mobile market dynamics are such that new requirements will arise quickly, forcing costly re-design of the chip set. As a result, processor developers have been slow to incorporate more than a few basic capabilities into their chip sets, creating a growing gap between the processor and the mobile system’s connectivity needs.

ArcticLink™ Solution Platform Addresses Connectivity Needs

QuickLogic® has addressed this connectivity gap with its new ArcticLink solution platform. The chip’s architecture gives mobile device developers an array of connection options, along with programmable fabric for customization that can be configured to work with most popular processors (see Figure 1).

Figure 1: ArcticLink Solution Platform Connectivity Capabilities

The device has three main sections. One section uses gate-array technology to provide highly popular interfaces such as USB with built-in high-speed PHY, SDIO and a configurable storage interface, enabling designers to determine the exact configuration the built-in logic adopts. A programmable fabric section provides a flexible processor interface that can support any number of popular applications processors. The third section is based on QuickLogic’s proprietary ViaLink® programmable technology. It is implemented in a 100,000-gate fabric that designers can configure with custom logic or interfaces from a pre-tested library of storage, networking, video and other system functions that QuickLogic offers. This combination of capabilities allows ArcticLink to replace as many as five discrete chips in a mobile system design.

A more detailed look at ArcticLink reveals the richness of its resource offering (see Figure 2). The USB interface section provides a single-port On-The-Go (OTG) controller with integrated PHY and a 12-signal ULPI interface with links to an optional CE-936 analog carkit port and a dedicated DMA controller. The storage host controller section can create a 1- or 4-bit SD/SDIO port, a 1-, 4-, or 8-bit CE-ATA port, or a 1-, 4-, or 8-bit MMC interface, all capable of achieving 52 MHz operation. The DMA engine manages data transfer from system memory (or 8 Kb of scratchpad SRAM) and dedicated buffer to achieve high throughput. The programmable fabric section uses wide-input logic blocks, which include seven, 4-kbit, dual-port SRAM blocks, and has a built-in FIFO controller. Independent clocking domains run the various sections, providing fine-grained control for active power management.

Figure 2: ArcticLink Architecture Block Diagram

One of the key strengths of the ArcticLink solution platform is the design flexibility it offers. The USB interface can provide USB 2.0 or 1.1 at high speed, full speed, or low speed. It can operate as a host, device or in a dual-role for USB OTG. Similarly, the storage controller supports SD memory card with SDHC, managed NAND, MMC 4.1 and CE-ATA for micro hard drives. The SDIO controller provides a link to Wi-Fi or mobile TV devices. The programmable fabric sections ensure that ArcticLink will connect seamlessly with processors families from Marvell®, Analog Devices, Freescale, TI and many others. The programmable fabric allows developers to implement virtually any other function or interface that their designs will require.

Application Examples

The versatility of ArcticLink can be seen by examining its role in various applications. A smartphone, for example, can be created using ArcticLink as the connectivity bridge between the application processor and peripheral functions (see Figure 3). In this case, the mobile device incorporates a Wi-Fi link for networking applications, a Bluetooth link for connection to headsets and other devices, a carkit interface over ULPI and a port connecting a mini hard disk drive for mass storage. A single ArcticLink device provides the connections to all these peripherals.

Figure 3: ArcticLink Smartphone Application Example

The exact same core hardware design can address a completely different set of requirements (see Figure 4). In this case however, the device offers a high-speed connection directly to a PC, a memory-card interface for storage, and a connection for mobile television along with the Bluetooth link. This ability to address different feature requirements with the same core hardware is one of ArcticLink’s major strengths.

Figure 4: ArcticLink Portable Navigation Application Example

Many other combinations are possible with this same core. A combination portable media player and personal navigation device for instance, may utilize a UART for connection to the GPS chipset, the USB link to connect with a PC, the SDIO to connect to Wi-Fi and CE-ATA in the programmable fabric to support a hard-drive connection. A design using the USB link to connect with Wi-Fi, the SDIO for a mobile TV interface and the programmable fabric to connect to a NAND Flash card is equally possible.

ArcticLink is a complete solution with IP, software driver, reference schematic, documentation and design services. This allows the designers to use ArcticLink as a standard device, yet the designer has the ability to customize the programmable fabric to meet his specific needs. This complete solution enables customers to accelerate their time to market and gain competitive advantages with differentiated products. QuickLogic also provides a development platform for ArcticLink, which is a daughter card to Sophia System's Sandgate III Marvell PXA3xx reference platform (See Figure 5).

Figure 5: ArcticLink Development Board

The current ArcticLink solution platform is only the first in a planned series of devices that will help development teams balance design flexibility, high-performance, and low-power in mobile applications. Future offerings will include programmable fabric devices with built-in image and video enhancement hardware for mobile television and devices with high-speed I/O interfaces for networking and other demanding applications. Such configurable system devices will become an essential part of the developer’s toolkit when dealing with the volatile and unpredictable consumer market.

By Howard Li, Senior Manager Connectivity Solutions, QuickLogic

March 22, 2007

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