Hierarchical symbolic sensitivity computation with applications to large amplifier circuit design

Recently significant research progress has been made toward the exact computation of symbolic transfer functions for large analog networks containing over 40 MOS transistors. A successful application of such a computation method for analog design requires an efficient method for ac-sensitivity analysis. It is addressed in this paper that the sensitivity of a transfer function to device sizes (or RC values) can be computed efficiently based on a hierarchical framework. It is demonstrated via examples that the ac-sensitivity can be used for improving the amplifier design metrics such as phase margin or pole/zero placement, etc.