Leonard Pelletier is the Application Support Manager for Freescale RF in Tempe, AZ and is in charge of providing technical assistance to the amplifier design community. He has been with the company since 1995 working in this position supporting any and all RF applications. Prior to his work with RF components, Mr. Pelletier held amplifier design engineering positions with both the Motorola Cellular Infrastructure Group in Arlington Heights, IL and the Motorola RF Products Division in Torrance, CA.
As a member of an application-support team, we regularly write and rewrite several application notes dealing with how to mount the RF transistors for maximum RF performance.
Through history, application notes such as AN1040, AN1041, AN1617, AN1673, AN1674, AN1907, AN1918, AN1923, and the latest versions of AN1949, AN3263 and AN3789, all deal with recommendations for device mounting.
Here in the Freescale Application Support Department, we get lots of calls from RF design engineers, who are in a desperate, crises mode. They have created a design using the best simulation tools possible and after having just built up their first prototype units, they are having some sort RF performance issues of varying degrees. Sometimes it is poor RF performance numbers not in line with the data sheet, sometime it is spurious oscillations, or shifting RF performance numbers with temperature or maybe even, in extreme cases, total device failures.
Most people working in the high power RF design arena think that they know a fair amount about high power RF products and the devices that comprise that market space. I am here to tell you that there are three relatively interesting and unknown facts about the high power RF product market that the consumers generally do not comprehend.
In the RF LDMOS semiconductor business, everything is constantly changing. The applications change, the device requirements change, the customer’s expectations change and of course, the competition changes.
In the semiconductor business, everyone is constantly revitalizing their portfolio, improving on the capability of their devices to make the next generation of parts significantly better than what is available now. Run faster, jump higher, PF flyers. The semiconductor business model is “innovate or die”. Either you are moving forward and winning or you are not-so-slowly dying. Competition drives the requirement for innovations and the fastest innovators typically have the best products, broadest portfolio base and the largest market share.