The RF3511 single-band linear power amplifier supports B1 (1920-1980MHz) in 3.4V, 50Ω mobile equipment designed for 3G UMTS transmit. RF3511 meets the spectral linearity requirements of HSDPA, HSUPA and HSPA+ with high power added efficiency. Two digital control pins selects high, medium or low power modes to optimize performance and current drain at different power levels. RF3511 integrates a directional coupler that eliminates the need for an external discrete coupler.