CMOS PAs pave the way for one-chip phones

摘要

The cell phone market has become one of the most competitive arenas in the semiconductor industry, with manufacturers producing more than 1 billion units annually. The argument has been made that specialty processes, such as gallium arsenide (GaAs), laterally diffused MOS (LDMOS) or silicon germanium (SiGe) bipolar CMOS (BiCMOS), with less-precise geometries, may offer the short-term cost advantage and linear modulation demanded by manufacturers and designers. The economies of scale inherent in CMOS, however, have driven the industry to make significant investments in this process, creating volumes that have outlasted, and will continue to outlast, any niche process offerings. For example, transceiver blocks previously realized in specialty BiCMOS processes from vendors such as Infineon, NXP and Skyworks have long since been implemented in CMOS - and, in some cases, integrated with the handset's main processor inside a system-on-chip.