A 3-V monolithic SiGe HBT power amplifier for dual-mode (CDMA/AMPS)cellular handset applications

摘要

A dual-mode (CDMA/AMPS) power amplifier has been successfullynimplemented by using a monolithic SiGe/Si heterojunction bipolarntransistor (HBT) foundry process for cellular handset (824-849 MHz)napplications. The designed two-stage power amplifier satisfies both CDMAnand AMPS requirements in output power, linearity, and efficiency. At Vncc=3 V,the power amplifier shows an excellent linearityn(first ACPR<-44.1 dBc and second ACPR<-57.1 dBc) up to 28 dBm ofnoutput power for CDMA applications. Under the same bias condition, thenpower amplifier also meets AMPS handset requirements in output power (upnto 31 dBm) and linearity (with second and third harmonic to fundamentalnratios lower than -37 dBc and -55 dBc, respectively). At the maximumnoutput power level, the worst power-added efficiencies (PAEs) arenmeasured to be 36% for CDMA and 49% for AMPS operations. The powernamplifier also tolerates severe output mismatch (VSWR>12:1) up to Vncc=4 V, with spurs measured to be <-22 dBc in CDMA outputsnat two specific tuning angles, but with no spur in AMPS outputs at anyntuning angle