Disclosed are high linearity CMOS-based devices capable of passing large signal and quiescent power amplifier current for switching radio frequency (RF) signals, and methods for biasing such devices. In certain RF devices such as mobile phones, providing different amplification modes can yield performance advantages. For example, a capability to transmit at low and high power modes typically results in an extended battery life, since the high power mode can be activated only when needed. Switching between such amplification modes can be facilitated by one or more switches formed in an integrated circuit and configured to route RF signal to different amplification paths. In certain embodiments, such RF switches can be formed as CMOS devices, and can be based on triple-well structures. In certain embodiments, a bias voltage applied to an isolated well of such a triple-well structure can be substantially tied to a source voltage coupled to source and drain, so as to yield desired performance features such as high amplification linearity even when the source voltage changes.