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RF & MICROWAVE DESIGN Ultra-Miniature | High Reliability Quartz Crystals, Oscillators and Sensors Medical Defense and Aerospace Industrial Come visit us at Electronica 2014 Hall B6, Booth 368 • H i g h e s t m e c h a n i c a l s h o c k s u r v i v a b i l i t y i n t h e i n d u s t r y • Military temperature range and beyond • Exceptional stability and precision • Ultra-low power consumption • Excellent long-term aging AS9100C ISO 9001:2008 CX4_GLASS_A CX16A CX18A CX9A CX11A CXOL_A STATEK CORPORATION 512 N. Main St., Orange, CA 92868 Tel. 714-639-7810 | Fax 714-997-1256 www.STATEK.com impossible to present the circuit or its components with out-of-spec voltages, temperatures, drive levels, impedance mismatches, and other potential disastrous errors. For more experienced users, there is an (ordinarily locked-out) “advanced mode” that eliminates most of these restrictions and allows the user to expand the use of the system. For example, test routines and other functions can be created in LabVIEW, in which the RF Power Tool can become part of larger system that includes other instruments. The system is targeted at two specific groups. In the first are the aforementioned manufacturers that do not have formidable (or virtually any) RF and microwave resources, such as appliance manufacturers, RF subsystem design companies, and manufacturers of heating, drying, and sealing equipment. Many of these companies are on the threshold of replacing vacuum tubes with solid-state amplifiers for the first time. The second group covers anyone who faces the problem of getting time on a full-up measurement suite, which transcends company size or market. The RF Power Tool system is small enough and required external components few enough that the evaluation process can be performed anywhere AC power is available. Fig. 2: The interactive display on the PC is the user’s window into all functions of the RF Power Tool. Freescale is currently developing evaluation boards that are compatible with the Power Tool system, which will ultimately be available for devices from 50W to 1.25 kW, and dedicated to various applications. The MHT1003N LDMOS RF power transistor was selected to be the first evaluation board, and was introduced last June because of its suitability for RF heating applications at 2450 MHz. It delivers 250 W CW with power added efficiency (PAE) of 58%, the highest for a silicon RF power transistor at this frequency. It also benefits from the excellent thermal performance of the company’s over-molded plastic packaging, that is better suited for automated assembly than air cavity ceramic packages. The device is also capable of withstanding substantial abuse, as it can deliver its full rated power when driven by twice its rated RF input power into a 10:1 impedance mismatch at all phase angles without degradation. The MHT1003N evaluation board lets a manufacturer of an RF heating product tailor the amplifier’s performance by adjusting its characteristics to match the properties of the heating cavity and antennas without first having to design the amplifier itself. Conversely, the company can monitor amplifier performance to see how it performs within an existing cavity and antenna structure. As the premise of the RF Power Tool system is to make it easier and far less expensive and complex to validate the performance of a specific device in a circuit, it was essential that it be more or less plug-and-play. The boards have sensors and other connectors that mate with the RF Power Tool, and the board and the device communicate information to establish device parameters, making the setup process painless. The user is guided by the system’s software that graphically shows the amplifier configuration on the board and the points on the board where changes to values can be made. – see figure 2. When a variable is modified, all other values dependent on it are also updated at more than 10 times per second. Changes in basic values and other parameters can be made using a thumbwheel and the small TFT LCD backlit display on the instrument’s front panel as well. While Freescale is just beginning the process of producing evaluation boards compatible with its devices, the company hopes that “smart” evaluation boards will become mainstream throughout the industry as they have with other technologies. This is especially important as industrial, scientific, and medical systems transition from vacuum tube RF power generation to solid-state amplifiers that promise much longer life, little or no maintenance, and ultimately lower total cost of ownership. As this is new territory for such companies, simplifying the evaluation and optimization process is essential to ensure that the transition occurs with as little angst as possible. The RF Power Tool system is one step is this direction, as it removes the need for deep knowledge of RF and microwave technology and the need to invest in discrete test equipment that can collectively cost more than $100,000. www.electronics-eetimes.com Electronic Engineering Times Europe October 2014 29


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