Power distribution synthesis for analog and mixed-signal ASICs in RAIL

The authors present new power distribution synthesis techniques that can handle realistic analog and mixed-signal performance concerns. The key ideas are to employ asymptotic waveform evaluation techniques to reduce complex macro, substrate, and package electrical models to accurate, low-order analytical expressions that can be quickly evaluated by a simulated annealing optimizer that selects and sizes the power bus topology while accommodating DC, AC, and transient constraints. RAIL, a new tool for power distribution, is used for this purpose. Experimental results demonstrate the importance of optimizing both topology selection and sizing, and the critical need to include transient as well as DC constraints during synthesis