Design of Stacked-MOS Transistor mm-Wave Class C Amplifiers for Doherty Power Amplifiers

Abstract

This paper discusses the design requirements of class C auxiliary (aux) amplifiers deployed in Doherty power amplifiers (DPA). Taking conduction angle and back-off (BO) level into account a global design chart is presented which can be utilized to properly dimension the aux amplifier. Based on the proposed method a class C power amplifier is designed and exploited in a DPA circuit at 28GHz which is evaluated using simulations based on 45nm CMOS technology. Simulations reveal 27dBm saturated output power, 60% maximum drain efficiency (DE), 45% DE at 6dB BO, and 2 times efficiency enhancement at 6dB BO which is a new record in this trend.

Efficient waveguide power combiners at mm‐wave frequencies

“…One of the most challenging aspect of mm-wave communication is related to the efficient generation of radio frequency power. Currently reported mm-wave power amplifiers (PAs) are unable to reach the required output power to account for the loss margins in commercial applications [1,2]. One typical way to increase the available output power is to combine the signals from multiple PAs using a power combiner.…”

Power management integrated circuit in audio and low power applications

“…Due to this, the class C power amplifier is not suitable for audio applications and will not be further discussed in this thesis. The class C amplifier is currently only used in RF applications [20,21], where instead of a resistive load, a parallel LC tuned circuit is used as the load. The resonant frequency of the LC tuned circuit can then be set to the input carrier frequency to recover the shape of the input signal.…”