Portable applications, also known as mobile devices, include many types of consumer handheld devices such as mobile handsets, smartphones, mobile Internet devices, portable media players, electronics toys/games, portable navigators, and digital camera/camcorders. Despite the economic downturn at the end of 2008, industry analysts predict demand for mobile devices and consumer electronics will continue to rise. The largest growth areas for mobile devices will be in mobile Internet devices, smartphones, and portable navigation.
Prepared to address this market trend, Altera introduced the MAX® IIZ CPLD, targeting low-power, low-cost handheld devices. Different from other markets, portable applications require a silicon solution with low power (for battery life-extension), low cost (typically $2 or less), and small packages (such as 5 x 5 mm or less). Designed with the market requirements of portable devices in mind, Altera's MAX IIZ devices consume almost zero power in standby mode, cost $2 or less in high-volume, and have a very small package size (package options for the smallest device can be less than 5 x 5 mm), making it one of the most attractive CPLD solutions in the market.
Because of its low power, low cost, and small package features, you can use a MAX IIZ device as a companion device to an ASSP or ASIC to help manage system processor power consumption or system boot-up sequencing. Other typical uses include I/O expansion, voltage level shifting, capacitive touch sensors, touch-screen encoders, key board decoders, color LED drivers, interrupt handling, or data processing. A unique feature only offered by MAX IIZ devices allows users to write security code into its internal user flash memory (up to 8 Kbytes). Figure 1 illustrates typical uses for MAX IIZ CPLDs in portable applications.
Figure 1. Typical MAX IIZ CPLD Uses in Portable Applications
System Power Management
Figure 2 shows an example of a MAX IIZ CPLD managing a portable device's system power. In this example, the MAX IIZ device takes 60 micro-seconds for a fast system boot up and reduces system power consumption with minimal standby current (29uA). With a wide-range of I/O voltage variation (1.5V, 1.8V, 2.5V, 3.3V), it can also function as three voltage level shifters. Its small package allows for a high system integration, and its programmability enables you to make last minute changes to the design. You can find more examples of using MAX IIZ devices in portable applications on the MAX II and MAX IIZ CPLD Design Examples web page.
Figure 2. System Power Management with MAX IIZ Device
Graphical LCD touch-screens are increasing prevalent in many portable applications, gradually replacing mechanical push buttons for a more contemporary, sophisticated human-machine interface (HMI). More recent implementations of touch technology utilize “multitouch” where you can use two fingers to manipulate an object, as on Apple’s iPhone.
Unlike ASSPs, MCUs, or other competitive technologies, MAX IIZ CPLDs deliver high I/O counts, ease of use, low power, low cost, small package, and the flexibility needed to implement a single or multitouch display for portable devices. Figure 3 shows a two-chip solution for multitouch design: the Analog Devices AD7142 integrated capacitance-to-digital converter and a MAX IIZ EPM240Z CPLD to expand the AD7142’s capability to handle two-dimensional ITO glass or film.
Figure 3. LCD Touch-Screen Display with MAX IIZ Device
Smartphones or Mobile Internet Devices
In addition to MAX IIZ devices, Altera also offers MAX II and MAX IIG CPLDs as well as the low-cost Cyclone® FPGA family, including Cyclone III FPGAs. Different from non-volatile CPLDs, FPGAs have built-in RAM, which allows them to perform digital signal processing (DSP) functions such as signal processing, image enhancement, or acting as the system's CPU.
Figure 4 shows an example of FPGA use in a smartphone or mobile Internet device.
Figure 4. FPGA Opportunities in Smartphones or Mobile Internet Devices
Portable Media Players
In a typical portable media player system (see Figure 5), the central functional block is the image processing controller. The basic functions required for the image processing controller can typically be implemented either in a digital signal processor or an ASIC/ASSP, but a companion PLD is often incorporated to allow for feature enhancements to enable a developer’s product differentiation strategy. The high pin counts and programmable features of CPLDs make them ideal devices for interface bridging between data formats or IO expansion when adding advanced features that are not available on the base platform.
CPLDs have also traditionally been used for board-level power management, voltage-level shifting, and DSP configuration functions. For portable systems, CPLDs maximize the system battery life by shutting down unused ICs in the system.
Finally, the non-volatile nature of CPLDs provides a way for developers to implement security functions for protection of content, user-specific information, and intellectual property (IP).
Figure 5. CPLD Opportunities in Portable Media Players Portable Media Players
Portable edutainment toys are educational toys that both teach and entertain children. The demand for these types of toys is growing because today's parents prefer toys that not only entertain but educate their children.
In a typical portable edutainment toy system (see Figure 6), the central functional block is the signal conditioning controller. The signal conditioning controller positions the motor based on inputs from an external sensor, processes and loads images to the display panel, handles audio processing functions such as audio tone synthesis, and manages external audio sources. Because these three functions are unique to the system specifications of the end product, a CPLD implementation provides a combination of benefits, including maximum design flexibility, low risk, and fastest time-to-market.
Similar to the portable media player application, CPLDs are ideal for interface bridging, I/O expansion, power management, voltage-level shifting, digital signal processing (DSP) configuration, and clock generation functions.
Figure 6. PLD Usages in Edutainment Toys