Large swing CMOS power amplifier

A CMOS class AB power amplifier is presented in which supply-to-supply voltage swings across low-impedance loads are efficiently and readily handled. The amplifier consists of a high-gain input stage and a push-pull unity-gain amplifier output stage. The amplifier dissipates only 7 mW of DC power and delivers 36 mW of AC power to a 300-Ω load, using standard power supplies of ±5.0 V. Lower impedance loads can be driven to higher power levels, providing the internal current limiting level is not exceeded.