- 22 June 2006 -

Freescale breakthrough in lower-cost plastic packaged high-power RF transistors

Freescale Semiconductor has launched what it claims is the industry's first 2GHz high-power RF transistors housed in over-moulded plastic packages delivering performance comparable to air-cavity flange packages. The advanced devices will be based on the company's high-voltage, seventh-generation (HV7) RF Laterally Diffused Metal Oxide Semiconductor (LDMOS) technology.

The RF technology is designed to give designers of cellular infrastructure the ability to reduce significantly the cost of base station amplifiers, which are the most expensive elements of wireless systems, while maintaining the stringent performance requirements.
Freescale's flagship HV7 device is the MRF7S19120N, available in a TO-270 WBL-4 package. The MRF7S19120N delivers a minimum of 120W P1dB and 36W average with typical performance anticipated to be 18dB gain, 32% efficiency and -37.5dBc linearity at PAR=6.1dB (tested with single-carrier W-CDMA signal with PAR=7.5dB @ 0.01% probability on CCDF). A corresponding family of 2.1GHz products is planned to be released in Q3 2006.

The MRF7S19120N is the first transistor to deliver comparable performance at 1.9 GHz with a minimum output power of 120W CW. When compared to its air-cavity counterparts, the achieved performance is equivalent in every electrical parameter.

Ceramic air-cavity packages have been used exclusively for decades to house high-power RF power transistors. They are inherently able to withstand and dissipate the high heat levels generated by the transistor, and they do not significantly degrade performance over that of the bare transistor die.

"Freescale is committed to complementing our air-cavity-packaged devices with cost-effective over-moulded plastic models that deliver exceptional performance," said Gavin Woods, vice president and general manager of Freescale's RF Division. "Over-moulded plastic-packaged devices can be much less expensive on a per unit basis than comparable devices in air-cavity packages, which provides a significant cost benefit to amplifier manufacturers. In addition, over-moulded plastic devices simplify our customer's manufacturing process by enabling a more efficient automated assembly, which can contribute additional cost savings."

Freescale has manufactured over-moulded plastic-packaged RF devices with parity performance up to 1 GHz for many years. However, achieving 2GHz performance in over-moulded plastic-packages identical to that of air-cavity packages requires complex design techniques and extensive work to overcome technology and materials limitations.
Samples of Freescale's MRF7S19120N are available now, and full production is expected to begin in Q4 2006.

www.freescale.com/rf