Patent ID: 6771109
Filing Date: 2004-08-03
Classification: H03K

Abstract:
A semiconductor device comprising:core circuitry including a first MOS transistor formed of a gate oxide film having a first film thickness, and receiving a first power supply voltage to operate; and interface circuitry including a second MOS transistor formed of a gate oxide film having a second film thickness thicker than said first film thickness, and receiving a second power supply voltage to operate; wherein said core circuitry provides an internal signal to said interface circuitry to define a logic level of an output signal and said interface circuitry includes: an output MOS transistor circuit including said second MOS transistor and connected to an output node to drive said output node according to said internal signal, and an activation circuit activating a parasitic bipolar transistor circuit associated with said output MOS transistor circuit according to an operation of said output MOS transistor circuit when a low voltage operation mode is selected by a mode select signal.