There has been a major shift in the cell phone market, with smartphones gaining prominence over feature phones in the past few years. The paradigm shift in phones has created market opportunities for other consumer products, such as e-readers and tablet computers.
E-commerce is driving additional market changes, as smartphones and other portable devices continue to evolve and as entire ecosystems grow up around them. In tandem with that evolution, power management ICs will progress and integrate more functions, yielding devices such as an audio codec with noise-canceling digital-signal processing, a microcontroller, more memory and system clocks.
Ultimately, the complete mixed-signal system-on-chip will mark the beginning of a new category of product—a Power SoC, perhaps. Such a chip, with an integrated microcontroller, will offer the flexibility (via firmware updates) to work across multiple platforms and device generations.
The smartphone paradigm shift has elevated the importance of high-performance analog and mixed-signal ICs while creating opportunities for suppliers of mixed-signal application solutions.
Even though smartphones are typically bigger than feature phones to accommodate the larger screens, they are often much thinner. In fact, the board size of today’s smartphones is only 40 percent that of older feature phones. To produce slimmer-profile phones, pc boards can no longer be stacked on top of the battery pack.
Smartphones’ multiple power-consuming functions—such as entertainment (gaming, videos and pictures), navigation and Web browsing—exacerbate the problem of constrained board space. That’s because such functions require an even bigger battery pack, further reducing available room.
Furthermore, today’s smartphones typically pack two major logic chips—the baseband controller and an applications processor for graphics, multimedia and other compute-intensive functions—plus several megabytes of memory and firmware. The rest of the phone often contains discrete components to handle all of the audio, battery and power management functions.
Smartphone makers must therefore find ways to meet the challenge of fitting more functions into smaller spaces.
The third socket
The only way to achieve this goal is to develop higher-integration devices. By integrating the required functions into a single chip that sits on the board (the “third socket”), developers can reduce parts count, save power and lower total system cost.
The industry is addressing the challenge through the development of high-integration power management chips that integrate all power, charging, interface and analog functions. Such chips require 40 percent less board area than the previous solutions.
These chips are more than just power management ICs. They are perhaps the beginning of a new category of device, one that fills the third socket in a cell phone or other portable platform. Indeed, the chips have to be flexible so that they can be used across multiple types of products (phones, e-readers, tablets and the like) for generations.
Looking forward, system designers should expect to encounter stricter power requirements as application processors move to faster clock speeds and as multicore processors require more power to satisfy consumers’ application and content cravings.
That means battery capacity will continue to increase, creating more headaches. Currently, that capacity is up to 1,500 milliampere-hours, but I would not be surprised to see it rise to 2,000 mAh. (Tablets, in fact, are now at 4,000 mAh and beyond.) Charging higher-capacity batteries could take twice as long. And with a bigger battery, board constraints in smartphones will become a major dilemma.
Companies such as Maxim Integrated Products are addressing these problems by delivering high levels of integration to minimize board space, lower the total bill of materials and improve performance.
Tunç Doluca is president and chief executive officer of Maxim Integrated Products Inc. (Sunnyvale, Calif.).