Abstract: Embodiments of the invention provide a logic simulation having a controllable delay model implemented therein that may be used to validate AC I/O loopback design in a pre-silicon environment by introducing delay models that allow the logic simulators to simulate analog behavior. For one embodiment of the invention, a fixed processor ratio is selected and delay statements of the hardware description language correspond to a specific time delay. These fixed values provide the ability to accurately determine and adjust delay in an analog simulation.

Abstract: Embodiments of the invention provide a logic simulation having a controllable delay model implemented therein that may be used to validate AC I/O loopback design in a pre-silicon environment by introducing delay models that allow the logic simulators to simulate analog behavior. For one embodiment of the invention, a fixed processor ratio is selected and delay statements of the hardware description language correspond to a specific time delay. These fixed values provide the ability to accurately determine and adjust delay in an analog simulation.

Abstract: According to one embodiment, a method of conducting a switching state (AC) loop back test at a buffer circuit comprises varying the relationship between the generation of strobe signals at a strobe input/output (I/O) circuit of a first group of I/O circuits and the reception of data at the first group of I/O circuits receiving the strobe signals fails, and comparing the time at which the first I/O circuit fails with a predetermined timing performance for the first group of I/O circuits. Subsequently, it is determined whether the first group of I/O circuits satisfies the predetermined timing performance.

Abstract: In one embodiment, an integrated circuit including a plurality of input/output (I/O) buffers is disclosed. The integrated circuit contains a plurality of I/O buffers. Each of the I/O buffers include an I/O test circuit that generates test pattern signals whenever the integrated circuit is operating in a loopback test mode. According to a further embodiment, the integrated circuit includes one or more programmable delay circuits coupled to the I/O buffers that permit switching state (AC) loopback timing tests to be conducted.