Pulse-Width Modulated CMOS Power Amplifiers

The relentless scaling of CMOS circuits has led to the possibility of completely integrated RF-SOCs, including the PA. A CMOS PA likely will not achieve the same peak output power and efficiency as its counterpart in a III-V technology. It is conceivable, however, that by taking advantage of the strengths of CMOS switching devices, future CMOS PAs can win in terms of average efficiency and, perhaps more importantly, cost. PWM techniques offer one such potential solution, owing to the level of digital integration possible. Because of this, PWM PAs are expected to scale well, and the dynamic range possible with such amplifiers should increase as well because the faster devices will be able to process signals with smaller pulse widths.