1. RF solid-state devices may soon find their way into the cooking appliances in our homes. (Courtesy of Ampleon)
LDMOS technology also is the driving force behind RF solid-state cooking (Fig. 1). Both NXP and Ampleon, who are at the forefront of this emerging niche, believe that solid-state technology can potentially replace the venerable magnetron-based microwave ovens.
“Using RF power transistors for solid-state cooking applications is high on the list of exciting new application areas for RF energy usage,” says Gerrit Huisman, marketing director at Ampleon. “Magnetrons have had a long life within our microwave ovens. We have all experienced the hot and cold spots they can create in our food. Thanks to recent technology developments, RF power transistors are now viewed as reliable and ideal candidates for microwave cooking applications.”
Huisman adds, “There is no doubt that the accurate power control of a solid-state device greatly helps to provide more control and stability in the cooking cycle. An oven’s operation can now set the cooking profile depending on what it finds in the oven, instead of blindly working to a user set-time.
“The power output, frequency, and appliance power efficiency will vary depending on, for example, whether a bag of popcorn is being cooked or a frozen chicken,” he says. “Cooking times are reduced by about 30% and taste is improved. Most importantly, homogeneously cooking is achieved. This means that food will not be over- or under-cooked. With added modern sensor technology, it is possible to constantly monitor, adapt, and optimize the cooking process.”
Higher Power Devices at Higher Frequencies
Suppliers are meeting the demand for high-power devices at higher frequencies, such as Ka-band, which is now commonly used for satellite-communications (satcom). GaN technology also has extended into this frequency range.
New Ka-band PAs have recently been introduced to the marketplace. For example, Qorvo unveiled its TGA2636-SM, a Ka-band, 3-W GaN PA for commercial very-small-aperture-terminal (VSAT) satellite ground terminals. The TGA2636-SM, housed in a 5- × 5-mm, surface-mount-technology (SMT) package, provides 25 dB of linear gain while achieving 30% power-added efficiency (PAE). The PA is fabricated using Qorvo's 0.15-μm gallium-nitride on silicon-carbide (GaN on SiC) process. The company says this process delivers three times more power density than previous-generation gallium-arsenide (GaAs) pseudomorphic high-electron-mobility-transistor (pHEMT) solutions.
MACOM entered the fray by unleashing its MAAP-011246 and MAAP-011139 Ka-band PAs. Both devices are offered in 5- × 5-mm, SMT packages. The MAAP-011246, which covers 27.5 to 31.5 GHz, provides 2 W of output power. The MAAP-011139 is a 4-W PA that spans 28.5 to 31.0 GHz. Both PAs are well-suited for next-generation Ka-Band VSAT systems.
Low-Noise Amplifiers in the News
Though high-power devices seem to be dominating, several new low-noise amplifiers (LNAs) have opened some eyes, too. A common theme among the latest LNAs is that external components are minimized significantly, thus turning them into convenient, low-cost solutions.
Sparking interest on this front is Custom MMIC’s new CMD223 LNA, which spans 9 to 18 GHz. It’s targeted at electronic-warfare (EW) and communication systems that demand small size and low power consumption. At 13.5 GHz, the CMD223 delivers more than 22 dB of gainand achieves a 1.5-dB noise figure.
Two new LNAs from Skyworks, the SKY65605-21 and SKY65611-11, are fabricated using advanced silicon-germanium (SiGe) BiCMOS technology. Both LNAs operate from 1.559 to 1.606 GHz, and are intended for Global Navigation Satellite Systems (GLONASS), BeiDou, Global Positioning System (GPS), and Galileo receiver applications. The SKY65606-21, for example, achieves a typical gain of 19 dB along with a noise figure of 0.6 dB.