Integrated circuitry and methods for reducing leakage current

Input/output circuitry includes a first PMOS device and a first NMOS device having first current electrodes are connected to each other and a pad. First selection circuitry, when the I/O circuitry is disabled, provides a first supply voltage to a control electrode and an N-well of the first PMOS device when the pad voltage is between the first and second supply voltages and to directly provide the pad voltage to the control electrode and the N-well of the first PMOS device when the pad voltage is greater than the first supply voltage. Similarly, second selection circuitry, when the I/O circuitry is disabled, provides a second supply voltage or directly provides the pad voltage to a control electrode and a P-well of the first NMOS device depending on whether the pad voltage is between the first and second supply voltages or less than the second supply voltage, respectively.