MTT-S 2007: Freescale Announces LDMOS RF Power Transistor
This transistor operates at 50V, offers distinct advantages over bipolar and MOSFET devices, and provides the power required for equipment such as magnetic resonance imaging (MRI) systems, CO2 lasers, plasma generators, and other systems.
The high gain reduces the number of parts required. This part count reduction decreases board space requirements and manufacturing complexity, ultimately resulting in lower amplifier costs.
"In delivering the MRF6VP11KH, we have set industry benchmarks in efficiency, output power, reliability and ease of design integration," said Gavin P. Woods, vice president and general manager of Freescale's RF Division. "No other RF power device, whether LDMOS, MOSFET or bipolar, can claim this achievement. We will continue to introduce innovative devices for this marketplace, enabling our customers to break new barriers in system performance."
Designed for operation from 10 to 150 MHz, the transistor leverages Freescale's sixth-generation, very high-voltage (VHV6) laterally diffused metal oxide semiconductor (LDMOS) technology . It joins a family of 50V VHV6 LDMOS devices announced in June 2006 to meet the demands of ISM applications operating at HF, VHF, and UHF frequencies up to 450 MHz.
"Freescale has broken the RF 1 kW pulsed power level with 50V LDMOS," said Lance Wilson, semiconductor research director for ABI Research. "The MRF6VP11KH's high gain, high efficiency, low thermal resistance and high output mismatch survivability are equally impressive."
The MRF6VP11KH delivers 65 percent drain efficiency and when combined with gain of more than 27 dB, this level of efficiency makes it possible to achieve reductions in amplifier design complexity, gain stages, parts count and circuit board real estate.
An application requiring 2 kW pulsed output power and 45 dB of gain typically requires a 15 W pre-driver, two 15 W drivers and eight final amplifiers when using MOSFETs or bipolar devices – a total of three stages and 11 devices. But a design based on the MRF6VP11KH requires only three devices. A single 10 W LDMOS driver and two MRF6VP11KH final amplifiers produce the same output power and a higher gain of 50 dB.
In addition, the 50V bias voltage employed by the MRF6VP11KH produces higher terminal impedances for a given power level, which makes the device easier to match into an amplifier circuit. The thermal resistance of Freescale's RoHS compliant, air-cavity package was measured at less than 0.13o C/W ?JC, providing efficient thermal management and reducing heat sink size. The MRF6VP11KH has integrated electrostatic discharge (ESD) protection, which eliminates the need for special handling procedures beyond those routinely observed in electronics manufacturing.
The MRF6VP11KH joins Freescale's family of 50V VHV6 LDMOS devices announced in June 2006. Additional devices for 10-to-450 MHz operation that are already in production include the MRF6V2010N (10 W CW, 24 dB gain, 62% efficiency), the MRF6V2150N (150 W CW, 25 dB gain, 68% efficiency), and the MRF6V2300N (300 W CW, 25.5% efficiency, 68% efficiency).
Samples of the MRF6VP11KH and a supporting reference design are available now from Freescale and production is expected to begin in Q4 2007.
SOURCE: Freescale Semiconductor