The embodiments described herein provide a radio frequency (RF) driver amplifier and method of operation. In general, the driver amplifier facilitates high performance operation in RF devices while being implemented with only n-type transistors. Using only n-type transistors in the driver amplifier can increase the operating bandwidth of the driver amplifier. Furthermore, using only n-type transistors in the driver amplifier can simplify device fabrication. The driver amplifiers and methods described herein can be used in a variety of applications. As one specific example the driver amplifier can be used in a switch-mode power amplifier (SMPA). Such a SMPA can be configured to amplify a time varying signal, such as an RF.