Motorola has introduced the first family of RF LDMOS devices optimized for 1.9 GHz PCS-band CDMA applications that offers a 50% improvement in single-ended power (up to 90 watts), a 25% improvement in efficiency, and superior gain performance. More significantly for CDMA designers, this new family, named the MRF19000 series, provides 30% more average power at the CDMA IS-95 mask than earlier generations of Motorola's RF LDMOS.

Based upon Motorola's fourth generation (HV4) RF LDMOS device technology, the MRF19000 series also provides maximum protection from hot carrier injection effects (<10% Vgs over 20 years), while at the same time not sacrificing RF performance. In addition, these devices incorporate input and output matching, making them easier to use and significantly reducing design cycles, as well as board space.

Finally, the complete lineup now includes an industry first integrated ESD (electro-static discharge) protection to simplify handling and reduce overall manufacturing costs associated with assembling ultra-sensitive devices. The 90-watt MRF19090 device, for example, is qualified as a Class 2, HBM (human body model) device with a 2,350-volt rating, and it qualifies as a Class-M3 300-volt device for the machine model. No other RF LDMOS device on the market has ever achieved such a high level of ESD protection.

"Not only do these devices provide more pure RF performance than any other device on the market, they also exemplify Motorola's commitment to enhance every area of device capability," said Daniel Artusi, vice president and general manager for Motorola's Wireless Infrastructure Systems Division (WISD). "By integrating the first ever ESD protection, they are easier to handle and assemble. And, of course, they do all of this without sacrificing the ruggedness, reliability, and consistency the industry has come to expect from Motorola. Our goal is to continue to push every aspect of performance, and the MRF19000 family does just that."

The first product to be unveiled in the MRF19000 line-up, the MRF19090, is the first ever single-ended, 90-watt device operating at 2 GHz. This device (available in package styles with and without the flange) is designed for Class AB narrowband CDMA (1.25 MHz wide channel) applications. Optimized to meet the IS-95 spec, the MRF19090 will be joined by the 60-watt MRF19060 and 30-watt MRF19030. The family also includes a push-pull, 120-watt MRF19120 for PCS microcell applications or advanced prototyping of CDMA2000 applications.

"In order to maximize the success of the IS-95 standard, the cost per voice channel must come down," said Randy Clark, WISD RF Power Infrastructure Product Manager. "That means getting more usable CDMA power out of the silicon people are buying now. Motorola's fourth generation RF LDMOS delivers that type of performance. Further, to help make the devices more usable, Motorola will begin to specify the Adjacent Channel Power Rejection Performance of the device on data sheets. We've spent a lot of time and energy proving that two-tone device performance does not necessarily equate to actual CDMA performance. To that end, we want to provide characterization data and figures of merit that are meaningful for the designers. The new family of PCS CDMA parts will do just that."

With another company making LDMOS announcements rather frequently I was beginning to despair of Motorola's possible responses. This family removes my despair rather nicely. The announced, initial, part, the MRF19090, provides the highest RF output from a single-ended device at 2 GHz and will take substantial business just from that specification. But there is much more here than that. RF engineers are extremely lax about static protection probably because most of us were brought up to worry about discharging the circuit instead of the individual. As a result a lot of parts are lost by careless handling in the field and at the prices involved it is not a trivial matter. Adding ESD protection to these devices is a large step forward.