65V LDMOS Technology Speeds RF Power Design
NXP Semiconductors N.V. today announced a new laterally diffused metal oxide semiconductor (LDMOS) technology for RF power transistors designed for operation up to 65V. This extra-high voltage LDMOS process will give rise to a new generation of products: the MRFX series. The new MRFX series and its flagship 1800W transistor focus on ease of use.
As RF becomes more pervasive in various industrial applications, NXP is providing RF power engineers with a means to reduce design cycle time: More power â€“ Higher voltage enables higher output power, which helps decrease the number of transistors to combine, simplifying power amplifiers complexity and reducing their size. Faster development time â€“ With higher voltage, the output power can be increased while retaining a reasonable output impedance. This simplifies the matching to 50 ohms, especially in wideband applications. Faster matching dramatically speeds up the development time.
Design reuse â€“ This impedance benefit also ensures pin-to-pin compatibility with current 50 V LDMOS transistors, making it possible for RF designers to reuse existing printed circuit board (PCB) designs for even shorter time to market. Manageable current level â€“ A higher voltage lowers the current in the system, limiting the stresses on dc power supplies and reducing magnetic radiation. Wide safety margin â€“ The NXP 65 V LDMOS technology has a breakdown voltage of 182V, which improves reliability and enables higher efficiency architectures.
The first product in the MRFX series is the MRFX1K80, the industryâ€™s most powerful continuous wave (CW) RF transistor. It is designed to deliver 1800W CW at 65V for applications from 1- to 470- MHz and is capable of handling 65:1 voltage standing wave ratio (VSWR).
â€œThe drop-in compatibility between our 1250-, 1500- and our new 1800-W transistors enables our customers to create a single scalable platform for multiple end products,â€ said Pierre Piel, senior director and general manager for multi-market RF power at NXP. â€œWith this new generation, we help our customers deliver on their commitment of higher performing, more rugged products in a shorter amount of time.â€
The MRFX1K80 is targeted for industrial, scientific and medical (ISM) applications such as laser generation, plasma etching, magnetic-resonance imaging (MRI), skin treatment and diathermy, as well as particle accelerators and other scientific applications. The MRFX1K80 is also designed for radio and very high frequency (VHF) TV broadcast transmitters. Industrial heating, welding, curing or drying machines currently using vacuum tubes will also benefit from the higher level of control that solid state enables.
The MRFX1K80H transistor in an air cavity ceramic package is currently sampling, with production expected in August 2017. Reference circuits for 27 MHz and 87.5-108 MHz applications are available now. In a few months, NXP will offer the over-molded plastic version, the MRFX1K80N, that reduces the thermal resistance by 30 percent for further reliability and ease of use.