A Closed-form Delay Estimation Model for Current-mode High Speed VLSI Interconnects

Abstract

Closed-form model for the delay estimation of current-mode Resistance Inductance Capacitance (RLC) interconnects in VLSI circuits is presented. The existing Eudes model for interconnect transfer function approximation is extended and applied for further accurate estimation of delay. With the equivalent lossy interconnect transfer function, finite ramp responses are obtained and line delay is estimated for various line lengths, per unit length inductances and load capacitances. The estimated delay values of extended Eudes model are compared with the existing Eudes model against HSPICE W-element model. The obtained delay values of Eudes model worst-case error percentage is 14.3% whereas our extended Eudes model is in good agreement with those of HSPICE results within 2% for the line lengths of 1mm to 10mm.