Patent ID: 6456472
Filing Date: 2002-09-24
Classification: H01L,H02H

Abstract:
A network for electrostatic discharge protection in a mixed signal integrated circuit, the network comprising:a global node; a plurality of circuit cells, each circuit cell having a VDD power supply pad, a VSS power supply pad, a pair of serially connected diodes poled to conduct current from said VSS to said VDD power supply pad, and an I/O pad connected to the junction of said serially connected diodes, and a Zener diode connected between the VDD and VSS pads, on breakdown to conduct current from the VDD to Vss pads, each circuit cell providing local electrostatic discharge protection within the cell; a coupling network for each circuit cell, each coupling network coupling a circuit cell to the global node; said coupling network comprising a pair of parallel connected oppositely poled diodes to allow current to flow in two opposing directions, the global node is coupled to an off-chip ground connection, and portions of the global node are physically positioned to separate each circuit cell from neighbouring circuit cells.