Patent ID: 7202701
Filing Date: 2007-04-10
Classification: H01L,H03K

Abstract:
1. A circuit coupled to an input-output bond pad (I/O pad) in an integrated circuit, the circuit comprising: an input buffer having an input terminal coupled to the I/O pad, an output terminal providing an input data value for the integrated circuit; an output buffer having a data input terminal coupled to receive a first data signal, an output enable terminal coupled to receive a first output enable signal, and an output terminal coupled to the I/O pad, the output buffer driving the I/O pad to a voltage level corresponding to the first data signal when the first output enable signal is asserted; a pad management circuit having a first input terminal receiving a second data signal, a second input terminal receiving a second output enable signal, and a third input terminal receiving a configuration signal indicative of the connection state of the I/O pad, the pad management circuit generating the first data signal and the first output enable signal, wherein the configuration signal has a first value indicating a normal mode where the I/O pad is to be connected to a package pin in an integrated circuit package and the configuration signal has a second value indicating an unconnected mode where the I/O pad is to be left unconnected in the integrated circuit package; and wherein when the configuration signal has the first value, the pad management circuit couples the second data signal as the first data signal and couples the second output enable signal as the first output enable signal; and when the configuration signal has the second value, the pad management circuit asserts the first output enable signal and generates the first data signal having a predetermined value.