使用TC1142偏置的GaAs功率放大器

RF bandwidths for cellular systems such as AMPS, TACS, GSM,

TDMA, and CDMA range from 800MHz to 1.0GHz. To provide RF

transmissions over this range of frequencies, Gallium Arsenide

(GaAs) has become the technology of choice and offers several

advantages over silicon technology: a much higher cutoff fre-

quency, higher breakdown voltage, lower noise figure, and higher

power-added efficiency. This translates to lower power dissipation

and longer talk time for cellular subscribers.AN808UsingtheTC1142forBiasingaGaAsPowerAmplifierAPPLICATIONCIRCUITAuthor:PatrickMaresca,MicrochipTechnology,Inc.Figure1showsatypicalapplicationcircuitforbiasingaGaAsPAinacellularsubscriberunit’stransmitter.Eachkeycomponentofthecircuitisdescribedbelow.INTRODUCTIONRFbandwidthsforcellularsystemssuchasAMPS,TACS,GSM,