We compare measured and simulated RF third-order distortion current, as well as the corresponding IP3, as a function of bias, for a SiGe heterojunction bipolar transistor (HBT), using MEXTRAM. The collector-base (CB) depletion capacitance model is identified to limit IP3 modeling accuracy near its peak. New CB capacitance modeling options are developed to significantly improve high-current IP3 modeling accuracy, particularly its peak behavior. Guidelines to simultaneous fitting of fT, fmax, IP3, and CBC are developed.

中文翻译：

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使用 MEXTRAM 改进 SiGe HBT 线性度的紧凑建模


我们使用 MEXTRAM 比较了 SiGe 异质结双极晶体管 (HBT) 的测量和仿真射频三阶失真电流以及相应的 IP3（作为偏置的函数）。集电极-基极 (CB) 耗尽电容模型被确定为将 IP3 建模精度限制在其峰值附近。开发新的 CB 电容建模选项可显着提高高电流 IP3 建模精度，特别是其峰值行为。制定了同时拟合 fT、fmax、IP3 和 CBC 的指南。