FDTD simulations for hybrid circuits with linear and nonlinear lumped elements

In this paper, hybrid circuits with lumped elements, including a capacitor, inductor, and diode, are analyzed with the finite-difference time-domain (FDTD) method, and alternative algorithms for FDTD simulations of those elements are proposed, respectively. An integral formulation for the capacitor and a differential one for the inductor make it possible that any concatenations of multiple lumped elements can be inserted into one Yee cell in FDTD simulations. An algorithm for the diode is also modified to extend the dynamic range of its 3-D FDTD simulation. Then, several hybrid circuits with different concatenations of lumped elements are analyzed by using the FDTD method. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 32: 408–412, 2002.