Competitive Landscape for Quad Band GSM Power AmpsRelated Terms:
Competitive Landscape for Quad Band GSM Power Amps - February 6, 2005
We interviewed engineers at several reputable power amplifier (amp) companies and present here a brief summary of what we learned.
The market for cellular handset power amps is both the largest and most competitive segment of the power amp business. In turn, the Global System for Mobile Communications (GSM) is the largest segment of the cellular handset market. Almost all new GSM handsets are now capable of using four different frequency bands (850, 900, 1800 and 1900 MHz, representing the GSM bands in use in Europe, parts of Asia, and most of the Americas). In our discussion we will therefore only consider four-band (or “quad-band”) GSM power amps.
The market for GSM cellular power amps is even more fiercely competitive than the wireless LAN power amp business. Prices and margins are constantly eroding. Complete modules with integrated passives sell for well under $0.70. Unlike the wireless LAN power amp case, however, the efficiency of the cell phone power amp does matter in battery life. GSM handsets transmit almost as much data as they receive. For example, if we consider average cell phone users, they talk as much as they listen. Furthermore, battery life on cell phones is a feature that interests consumers and on which cell phone manufacturers can differentiate.
Therefore, cell phone power amp manufacturers have already invested a great deal to increase the efficiency of their products. Existing GSM power amps that are shipping in volume today, have typical efficiencies of about 55%, and can reach as high as 63%.
Similarly to wireless LAN power amp modules, the packaging costs of a cell phone power amp module is comparable to the die cost, while the “packaging-plus-test” costs exceed the die cost. This means that the overall cell phone power amp manufacturing costs also cannot be reduced by simply reducing the die size (and hence cost). Moreover, the industry already uses very tiny die sizes for wireless power amplifier products, mostly in the range of 1 mm2 to 1.5 mm2. Huge numbers of die per wafer are already being produced, so there is minor advantage to be found through further miniaturization.
It takes about 1.5 to 2 years for an established cell phone power amp company that has an existing and productive working relationship with a cell phone handset maker to transition a new idea from the first laboratory demonstration to a design that can be manufactured in high volume. Handset makers are very conservative and prefer using approved and well-tested designs. For a handset maker, a recall of millions of cell phones caused by a minor defect in the power amp (a 70 cent component) is a disaster scenario to be avoided at all costs.
The prevalent attitudes are:
If it’s not broken, why fix it?
If it doesn’t affect our costs, then why take any risks?
The conservatism in the cell phone industry makes it difficult for power amp startups to get in the door to have their new designs tested and evaluated. The dire consequences of component failure make it even more difficult for power amp startups to qualify their products with key, high volume customers. Typically, starts take much longer to achieve high volume sales, owing to their lack of credibility and young track records.
In addition, the economics of volume manufacturing heavily favor the established players. Power amp startups and new players pay large premiums for wafers, packaging, and testing. Initially, they also buy in smaller volumes, which can further exacerbate the cost problem. Unless a new entrant to the market has at least a 2X inherent cost advantage to offset the inevitable manufacturing disadvantages, he/she doesn’t have a fighting chance.
Note that this commentary comes directly from discussions with people from well-established power amp companies, and from someone who has started a power amp company – interestingly enough, all parties said the same thing. The links below lead to companies that are active in the wireless power amplifier market. We present examples of part numbers, typical performance (specifically efficiency), and data sheets. Note that nearly all of the products here have been available for a year or more. No future products are included in this list.
Anadigics has a 55% (AWT6146) efficiency quad band GSM power amp.
RF Micro Devices has a 55% (RF3133) and a 63% (RF3177) efficiency quad band GSM power amp.
Freescale Semiconductor has a 43% (MMM6025) efficiency quad band GSM power amp.
TriQuint Semiconductor has a 58% (TQM7M4022) efficiency quad band GSM power amp.
Fairchild Semiconductor has a 55% (RMPA1850) efficiency quad band GSM power amp.
Skyworks has a 53% (SKY77316) efficiency quad band GSM power amp.
Myungmin has a 54% (CX77312) efficiency quad band GSM power amp.
PhD thesis from 2003 which discusses (simulated) 90% efficient class-D GSM. It is interesting in that it references papers back to 1996 on high-efficiency class-D and class-E RF power amps.