Q波段2W平衡式GaAs pHEMT功率MMIC

2W Q-band Balanced GaAs pHEMT Power Amplifier MMIC

报道了一款采用0.15μm GaAs功率MMIC工艺研制的Q波段平衡式功率放大器芯片。芯片采用Lange耦合器进行功率合成。在该平台工艺规则限制条件下,按照传统设计方法设计的Lange耦合器无法满足平衡式放大器设计需求。文中提出了解决方法,对Lange耦合器的端接阻抗进行优化,使得设计的Lange耦合器物理尺寸符合工艺规则要求。放大器采用三级放大拓扑结构,同时综合应用三维和平面场仿真技术,提高电路仿真精度。芯片在43~46GHz频带范围内、6V偏置、连续波工作条件下,饱和输出功率大于33dBm,效率大于15%,功率增益大于14dB,线性增益为16dB,线性增益平坦度小于±0.8dB,芯片面积3.9mm×4.8mm。

A Q-band balanced power amplifier MMIC fabricated in 0.15μm GaAs pHEMT technology was presented.Power combination of the MMIC was implemented by using a Lange coupler.Under the design rule of 0.15μm GaAs pHEMT technology,traditional design method of the Lange coupler could not satisfy the application requirement of balanced power amplifier.For this,a novel design method of optimizing load impedance of the Lange coupler was presented,which solved the conflict between microwave performance and technology rules.Three stage topology and 3D/2.5D EM simulations were adopted in the power amplifier design.The MMIC operated in CW mode.An output power over 33 dBm with a power gain over 14 dB and a power added efficiency more than 15% are achieved at 43~46 GHz and a drain voltage of 6 V.The MMIC also demonstrates an 16 dB small signal gain and a±0.8dB gain flatness across the band.The chip size is 3.9mm×4.8mm.