A circuit includes a first CMOS device forming a gain stage of a power amplifier and a second CMOS device forming a voltage buffer stage of the power amplifier. The first CMOS device includes a first doped well formed in a substrate, a first drain region and a first source region spaced laterally from one another in the first doped well, and a first gate structure formed over a first channel region in the first doped well. The second CMOS device includes a second doped well formed in the semiconductor substrate such that the first doped well and the second is disposed adjacent to the second doped well. A second drain region and a second source region are spaced laterally from one another in the second doped well, and a second gate structure formed over a second channel region in the second doped well.