5v tolerant I/O circuit

摘要

An integrated circuit has an I/O circuit that is connected to an I/O PAD. The I/O PAD may have greater voltage than the VDD associated with the integrated circuit so there is provided a switching circuit that is connected between the VDD and the I/O PAD. An output circuit is also provided that comprises n-channel transistors connected between the PAD and the ground. There is a cascode arrangement of p-channel transistors connected between the I/O PAD and VDD.