A high-voltage output buffer fabricated on a 2 V CMOS technology

VLSI core voltages have scaled considerably below legacy I/O standards such as PCI which require tolerance of voltages between -1 V to over 6 V when power supply deviation and signal overshoot effects are considered. Circuit based dielectric protection has been demonstrated previously to address this problem for 3.3 V on a 2.5 V process. Gate oxide stress is dependent on the total stress time and magnitude of the stress over the life of the chip, which must be limited. Here, a 5 V PCI output buffer implemented on a standard 2 V process is presented which dynamically limits the DC stress to devices below 2.1 V and minimizes AC stress duration.