- 5 March 2006 -

RF Switch and MEMS set to disrupt cellphone business

Strategy Analytics, the research and consulting company, continues to keep a watchful eye on the key trends in markets such as mobile comms. A distinguishing part of this service is the attention to the details of the component supply sector of that industry. Recently, the company has published its conclusions concerning not only the RF switch segment but also that for RF MEMS for cellphones. Their findings make for interesting reading.

In its latest Insight report, "Silicon-on-Sapphire Switches for Handsets: Stopgap or Disruptive Technology?" Strategy Analytics evaluated CMOS silicon-on-sapphire (SoS) RF switches. It found that SoS has begun to disrupt established approaches to transmit-receive (T/R) switching in multi-mode, multi-band cellular handsets.

Notably, Peregrine Semiconductor has shipped several million CMOS SoS RF switches to customers for GPRS handsets. Recently, the company released SP7T "HaRP" SoS RF switches for dual-mode W-CDMA handsets, claiming that these offer superior performance to GaAs p-HEMT switches.

"After evaluating this technology, we have concluded that Peregrine's SoS RF switches offer advantages that could displace GaAs in dual-mode WCDMA handsets," says Asif Anwar, Director of the Strategy Analytics GaAs service. "However, GaAs vendors have already moved to address p-HEMT switch shortcomings with improved performance. They have also developed switches with higher complexity not yet available in CMOS on SoS. These moves will limit the penetration of CMOS SoS in applications now served by p-HEMT switches to a few design-wins at best."

"CMOS SoS will continue to have its greatest success in displacing p-i-n diodes in antenna switch modules," adds Chris Taylor, Director of the Strategy Analytics RF and Wireless Components (RFWC) Service. "The multiple p-i-n diodes required for complex antenna switch modules (tri- and quad-band) draw significant current. Peregrine has already demonstrated the suitability of its technology for this application."

Secondly, in its evaluation of RF MEMs technology, the Strategic Technologies Practice at Strategy Analytics has recognized WiSpry's MEMs varicap (variable capacitor) as a practical device that could reduce handset bills of material.
This technology evaluation is found in the Strategy Analytics' Insight report, "WiSpry Claims First Practical RF MEMS for Cellphones."

WiSpry's first product, a varicap duplexer, scheduled for production release in Q1 2006, is a two-state, tunable notch filter suitable for CDMA and W-CDMA handsets. WiSpry plans to release other products based on its
technology, including RF MEMs switches and Power Amplifier (PA) modules.

"While it is difficult to predict WiSpry's ultimate success in the cellular handset market, this company appears to have developed a practical MEMS device with compelling benefits," says Chris Taylor. "If it performs as claimed, WiSpry's varicap would reduce the number of passive components needed in handsets and enhance the performance of antenna switch modules (ASMs), PAs, and transceiver modules."

Asif Anwar adds that, "On the other hand, offering complete PA modules seems unwise given the competitive nature of the market, and the dominance of large, established, GaAs and LDMOS vendors such as RF Micro Devices, Skyworks and Renesas Technology. Such a move would put WiSpry in direct competition with its
customers."

Web: http://www.strategyanalytics.com