This paper presents a general method for computing transient sensitivities using both direct and adjoint methods in controlled explicit event driven simulation algorithms that employ piecewise linear device models. Sensitivity information provides first order assessment of circuit variability with respect to design variables and parasitics. This information is particularly useful for noise analysis, timing rule generation, and circuit optimization. Techniques for incorporating transient sensitivity into adaptively controlled explicit simulation, a general piecewise linear simulator, are presented. Sensitivity computation includes algorithms to handle instantaneous charge redistribution due to the discontinuous conductance models of the piecewise linear elements, and the loss of simulation accuracy due to the nonmonotonic responses in autonomous adjoint circuits with nonzero initial conditions. Results demonstrate the efficiency and accuracy of the proposed techniques.

This paper presents a general method for computing transient sensitivities using both the direct and adjoint methods in event driven controlled explicit simulation algorithms that employ piecewise linear device models. This transient sensitivity capability is intended to be used in a simulation environment for transistor level analysis and tuning. Results demonstrate the efficiency and accuracy of the proposed techniques. Examples are also presented to illustrate how the transient sensitivity capability is used in timing characterization and circuit tuning.