Global Designer: Low-cost handsets gain traction in India

Burgeoning demand from mobile-service operators for ultralow-cost handsets to service price-sensitive emerging markets, such as India, is motivating semiconductor vendors to develop single-chip-handset offerings. For example, Texas Instruments recently demonstrated the first less-than-$40 handsets built in India from concept to design to production. BPL Ltd (www.bplmobile.com) and Quasar Innovations (www.quasarinnovations.com) based the Primus GSM phones that they developed on TI's TCS chip set. These handsets incorporate only basic voice and short-message service-no cam- eras, color screens, or MP3 players, instead emphasizing low cost and an intuitive user interface.

"We expect the industry will be selling an ultralow-cost mobile phone for less than $20 by the start of 2006. These costs include electronic components, connectors, the pc board, the casing with display and keypad, software, and the battery," says Horst Patch, vice president of the Communication Business Group at Infineon Technologies.

Ultralow-cost handsets will enable telephony in parts of the world in which land-line service is unavailable or unreliable, says Douglas Grant, business-development manager with Analog Devices' RF and Wireless Systems Group. Grant adds that chip-set suppliers pursuing the ultralow-cost-handset market need to provide robust reference platforms and even complete turnkey designs with preloaded software features to simplify the development of the final handset product.

"In phone design, there are a few major building blocks-among them: digital baseband, analog baseband, RF section, and memory, which comprise the bulk of the cost drivers for these handsets," explains Harish M, general manager of business development at TI India. An ultralow-cost handset should have no more than 100 components, compared with 600 or more for a high-end feature phone or smart phone.

Grant says that manufacturers can reduce BOM (bill-of-materials) costs by integrating core handset functions, such as digital and analog processing, power management, and a radio transceiver, into one chip. But this approach is risky, because it requires a high-performance wafer process, and may be unsuited for consistent production. "A lower risk approach is to combine functions into a system-in-package design, which saves board area and manufacturing cost but retains the performance of the radio and minimizes risk because vendors can easily port software to such a device," says Grant.

Infineon's new, low-cost E-Goldradio handset combines the baseband processor and the RF transceiver in a 9×9-mm-footprint chip. It enables manufacturers to implement the baseband and RF functions on less than 4 cm² of board space-about 30% less than two-chip offerings require. It also cuts the BOM cost by about 30% by eliminating external components, including capacitors and discrete components, that a two-chip approach requires. And a low-component-count design and simplified layout enable the use of cheap, four-layer pc-board technology and single-side mounting, further reducing manufacturing costs. TI also offers the similar single-chip DRP (digital-radio processor).

Analog Devices, www.analog.com.

Infineon, www.infineon.com.

Texas Instruments, www.ti.com.