While IEEE’s decision to move next year’s International Microwave Symposium, IMS 2007, across the pacific to Honolulu, Hawaii, was exhilarating to many attendees, plenty of innovative products introduced last week at ISM 2006 in San Francisco, Calif., sparked new interest in the engineering community. From gallium nitride (GaN) HEMTs to broadband antenna and novel integrated test and measurement equipment, developers demonstrated a variety of products and technologies for a broad range of existing and emerging communications, medical, industrial and military applications.
On the GaN front, Cree Inc. (www.cree.com) and Eudyna (www.eudyna.com) were showcasing much higher power levels than previously reported by these manufacturers. Cree, for instance, disclosed a high-power GaN transistor with 400 W of peak pulsed power at 3.3 GHz with 10.6 dB associated power gain and 62% drain efficiency when operated at 40 V. According to Jim Milligan, Cree’s product manager for wide bandgap RF products, upcoming mobile WiMAX applications are expected to require average orthogonal frequency-division multiplexing (OFDM) output power between 10 W and 25 W with peak-to-average ratios (PAR) as high as 12 dB. This will require transistors that are capable of delivering up to 400 W of peak RF output power. The manufacturer is planning to sample these new versions of its wide band gap GaN transistors later this year. Likewise, Eudyna boasted some 500 W of peak pulsed power capability for its GaN devices.
RF Micro Devices (www.rfmd.com) demonstrated a digitally predistorted linearized four-stage power amplifier based on its GaN high electron mobility transistors (HEMTs) for WCDMA. This four-stage amplifier comprised two pre-drivers, one driver and one high power amplifier (HPA) with total out power rated at 12.5 W at 2.1 GHz. According to RFMD, its high-power 28 V/48 V 0.5 μm GaN process will undergo qualification in September. It is expected to be completed by March 2007.
Competitors Freescale Semiconductor (www.freescale.com) and Infineon (www.infineon.com) continued to expand their LDMOS portfolio. By the way, analysts predict that silicon LDMOS transistors will continue to dominate the wireless infrastructure scene for the next couple of years. Thus, Freescale continues to expand its portfolio of LDMOS devices, while Infineon unveiled its next-generation LDMOS in plastic packaging for wireless infrastructure PAs. Simultaneously, a new generation of gallium arsenide (GaAs) heterojunction bipolar transistors (HBTs) were also released at the show as a competitor to LDMOS.
WJ Communications (www.wj.com) disclosed a new line of 28 V InGaP/GaAs HBTs for mobile infrastructure applications. The developer flaunted its improved ACPR/ACLR performance at equivalent or higher efficiencies than LDMOS. Other HBT backers to display new devices include TriQuint Semiconductor (www.triquint.com).
In the CMOS RFIC arena, Analog Devices (www.analog.com) released a quadrature modulator that operates from 50 MHz to 2.2 GHz for low IF and RF applications such as broadband wireless access systems, microwave radio link transmitters, cable modem termination systems and cellular infrastructure. Requiring only a single-ended, two-times local oscillator (LO) input, the ADL5385 converts complex modulation information from the baseband to the final RF input over a broad range of LO frequencies.
STMicrolectronics (www.st.com) showed an integrated multi-band RF synthesizer with on-chip PLL and VCO, enabling a single chip to operate up to 4.5 GHz. Atmel (www.atmel.com) introduced a single package GPS receiver with highest sensitivity and low power consumption. Developed in collaboration with u-blox AG, the ATR0635 boasts a high tracking sensitivity of –158 dBm.
Likewise, the compound semiconductor users had plenty to offer. For example, analog IC supplier Inphi Corp. (www.inphicorp.com) unveiled an indium phospide (InP) based 18 GHz track-and-hold amplifier (THA) IC with a sampling rate up to 2 Gsps. And Hittite Microwave (www.hittite.com) released a SiGe BiCMOS-based 4.5 GHz THA with high linearity. The wideband HMC660LC4B is the first product within Hittite’s new data converter product line. It is designed for direct sampling of full-scale 1 Vpp signals with up to 4.5 GHz input bandwidth with a maximum 3 GHz clock rate.
That’s enough for now. More to come next week on test and measurement equipments and microwave/millimeter wave components.