应用于射频前端的高Q值SiGe HBT有源电感

A High Q SiGe HBT Active Inductor for RF Front-End Applications

针对传统的共基-共射(CB-CE)回转器有源电感的品质因子Q值低等缺点,应用Cascode结构把CB-CE有源电感改进为共基-共射-共基(CB-CE-CB)有源电感,推导出等效电路及等效阻抗表达式。最后基于Jazz 0.35μm SiGe BiCMOS工艺,利用ADS软件完成电路设计与仿真,应用Cadence Virtuoso平台完成版图设计。改进之后的有源电感,通过改变外加偏置条件,实现了电感值和品质因子Q值的可调,电感值可调范围为0.35～2.72 nH,Q值最大值可达1 172,版图面积仅为51μm×35μm。该有源电感应用于射频电路中,可取代无源电感。与无源电感相比,品质因子Q值明显提高,版图面积大大减小,更利于集成。

For the low Q-factor of the common base-common emitter （CB-CE） active inductor based on gyrator, the CB-CE active inductor was improved to be the common base-common emittercommon base （CB-CE-CB） active inductor by applying Cascode circuit, the equivalent circuit and impedance expression of the improved circuit were derived. Based on Jazz 0.35 ~m SiGe BiCMOS process, the improved active inductor circuit was designed and simulated by ADS, the layout was designed by Candence Virtuoso. The result shows that the inductance value and Q-factor of the new active inductor can be tuned by adjusting the bias condition. The tunable inductance value is in the range of 0.35 - 2.72 nil, the maximum quality factor can reach 1 172, the area of the layout is about 51μm × 35 μm. The passive inductor can be substituted by the active inductor in RF circuits. Compared with the passive inductor, the Q-factor of the active inductor is higher and the layout size of the active inductor is significantly reduced, which makes the integrating of the circuit much easier.