"3.5G handset OEMs are demanding small, affordable, multi-band HSDPA / WEDGE RF solutions. The SW3200 delivers on all of these requirements and greatly simplifies multi-band 3.5G radio systems to ensure a fast time-to-market for handset manufacturers," said Michael J. Hogan, President and CEO of Sirific Wireless. "Our expertise in advanced RF CMOS design and direct conversion architectures allows us to achieve the highest levels of RFIC integration that result in the mobile industry's smallest multi-band HSDPA / WEDGE RF solution with a board area savings of more than 150% over the competition."

The SW3200 RF transceiver supports transmit and receive operation in five WCDMA bands (I, II, III, IV and V), as well as all four EDGE, GPRS, and GSM bands. With HSDPA Category 9 capability, the SW3200 enables downlink data rates up to 10.2 Mbits/s. It also incorporates a patented sigma-delta fractional-N synthesizer design that requires no external loop filter components. An on-chip 26-MHz digitally controlled crystal oscillator (DCXO) completes the SW3200's extensive feature list.

To accommodate a variety of WEDGE baseband configurations, the SW3200 features a flexible baseband interface. This versatile RF transceiver supports next-generation baseband processors with a 2.5G DigRF-compliant digital baseband interface, which incorporates all GSM / EDGE analog baseband processor functions. The SW3200 also provides an analog interface for legacy WEDGE baseband processors.

Sirific Wireless applies a product-proven, linear direct up-conversion architecture in the SW3200's multi-band transmitter design. This low-noise linear transmitter requires no external Tx filtering for GSM/EDGE transmission and directly interfaces to standard linear power amplifiers. The SW3200's direct down-conversion receiver supports concurrent WCDMA and GSM / EDGE operation, as well as compressed mode receive operation for smooth handoff between WCDMA and GSM / EDGE networks.

"Highly integrated, single-chip CMOS RF transceivers are an absolute requirement for feature-rich, thin-profile 3.5G mobile phones, in which board space is at a premium to accommodate complex multimedia functionality," said Will Strauss, President of Forward Concepts. "The WCDMA handset market is expected to grow to over 80 million units in 2007. Sirific Wireless, with its NEXUSTM III family of single-chip CMOS 3.5G RF transceivers, is positioned to be a significant contributor to the acceleration of this market."

By leveraging the advantages of 130-nm CMOS technology, Sirific Wireless has maximized integration in the SW3200 while reducing size, cost and current consumption. When coupled with a multi-band radio front-end that supports quad-band GSM / EDGE and tri-band HSDPA / WCDMA, the SW3200 creates a complete radio solution that is only 7.0 cm2, more than 150 percent smaller than the competition.

"If you look at transceivers today, they all have different requirements for manufacturability," observes Kiran Konanur Vice President, Sales & Marketing at Sirific Wireless. "There is a great deal of talk about polar loop architectures, but they require a significant amount of testing in the manufacturing test line to get the handset qualified. Instead, we have implemented a low-noise, wide-band direct up-/down-conversion architecture that is very simple to calibrate on the transmit side."

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The team agrees that their greatest design challenge with this chip was implementing it in CMOS. "It takes a great deal more design time to work in CMOS and meet cellular standards," explains Konanur, "That's why most transceivers are in BiCMOS." Sirific Wireless works with TSMC and has implemented the SW3200 in 0.13 micron CMOS.

In terms of size, the design team at Sirific Wireless responded to the increased functionality in 3G phones by bringing as much functionality on chip as possible and paring the device size down to 7 mm x 7 mm x 1 mm. The SW3200 integrates a quad-band GSM/EDGE transceiver, a multi-band HSDPA/WCDMA transceiver, an on-chip sigma-delta fractional-N synthesizer design that requires no external loop filter components, and an on-chip 26-MHz digitally controlled crystal oscillator (DCXO). When it comes to power, the device draws 115mA of current (Receiver + Transmitter) in WCDMA mode, which the company reports is a more than 15-percent improvement over the competition.

The end design does not skimp on performance either; here are some key technical parameters:

• Using the SW3200, a handset manufacturer can achieve a GSM receive sensitivity of -113dBm at the LNA input.
• The SW3200 includes a WCDMA receiver with an EVM of 8 percent, which enables HSDPA (CAT 9) downlink data rates of up to 10.2Mbits/s.
• The SW3200's WCDMA transmitter exhibits an EVM of <4percent over the entire output power range

So, how did they do all this? The team at Sirific has been very busy developing new techniques and intellectual property (IP). Even though this is its first product, the young company already boasts 7 patents and 64 pending. "IP allows us to achieve very low noise output in our GSM/GPRS transmitter, and removed the requirements for transmit SAW filters," says Konanur. The company also has IP in the receiver to achieve the EVM for HSDPA data rates and IP in the synthesizer which removed the requirements for any external components on the loop filter.

Evaluation Board for the SW3200

For designers of next-generation handsets, the SW3200 is surely worth a closer look. It is a "real" device and is sampling now. Pricing begins at $7.95 in 10K unit quantities.Click here for more information.

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