Patent ID: 6586974
Filing Date: 2003-07-01
Classification: H03K

Abstract:
An output driver for driving a signal onto a pad of an integrated circuit, comprising:a level-shifter which receives a core-level data signal indicating a logic value based on a core power supply levels, and generates an I/O-level data signal indicating a logic value based on an I/O power supply levels; a pre-driver circuit which receives said I/O-level data signal and generates a pre-drive signal having a drive state indicating to drive said pad and a non-drive state indicating not to drive said pad; a drive device responsive to said pre-drive signal which drives said I/O-level data signal onto said pad when said pre-drive signal is in said drive state; and a driver disabling circuit which disables said drive device from driving said pad when said I/O power supply is powered up and said core power supply is powered down.