In this work a two-stage class-AB complementary metal oxide semiconductor radio frequency (CMOS RF) power amplifier is designed and tested according to global system for mobile communications-enhanced data rates for GSM evolution (GSM-EDGE) requirements. The amplifier efficiency is improved by using a DC-DC converter that lets the power supply voltage track the envelope of the input signal. The amplifier stability is improved by implementing an on-chip ground separation technique. The ground separation technique is based on separating the grounds of the amplifier stages on the chip and thus any parasitic feedback paths are removed. Simulation and experimental results show that the technique makes the amplifier less sensitive to bondwire inductance, and consequently improves the stability and performance.