Design of SiGe HBT power amplifiers for microwave radar applications

SiGe;Mutual thermal coupling;Mixed breakdown cascode architecture;Power amplifiers

Andrews, Joel ; Electrical and Computer Engineering

University:Georgia Institute of Technology

Department:Electrical and Computer Engineering

关键词: SiGe;    Mutual thermal coupling;    Mixed breakdown cascode architecture;    Power amplifiers;   

Others  :  https://smartech.gatech.edu/bitstream/1853/28116/1/andrews_joel_m_200905_phd.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

A novel modification to the standard cascode amplifier architecture is presentedin SiGe which allows for an optimal separation of gain and breakdown functions throughthe mixed breakdown cascade architecture, opening the door for moderate poweramplifiers in SiGe. Utilizing this technique, a two-stage, high-gain amplifier operating atX-Band is fabricated and measured. The 20 dB of gain per stage represents the highestgain at X-Band at the time of publication. Additionally, a near one Watt power amplifieris designed and fabricated at X-Band, which represents the highest output power in SiGeat X-Band at time of publication. Related to the power amplifier design, thermalconsiderations are also investigated. The validity of utilizing lumped mutual thermalcoupling in SiGe devices is presented. Using this finding, a thermal coupling model andnetwork which are compliant for use with commonly available HBT models and circuitsimulators is presented. This model and network is used to thermally optimize SiGe PAcells based upon layout spacing.