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: Various apparatuses and methods to generate a clock signal that controls data operations in an integrated circuit. In an embodiment, a circuit for generating a clock signal that controls data operations in an integrated circuit includes a first clock synthesizer, a divider circuit, and a second clock synthesizer. The first clock synthesizer produces a first signal derived from an external reference signal. The first signal has a first frequency that is greater than a frequency of the external reference signal. The divider circuit divides the frequency of the first signal by N, where N is an integer greater than 1. The divider circuit outputs a second signal having a second frequency which is equal to the first frequency divided by N. The second clock synthesizer couples to the divider circuit for producing the clock signal at a frequency which is an integer multiple of the second signal. The second clock synthesizer also produces a strobe signal.

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.

Abstract: According to one embodiment, an integrated circuit is disclosed that includes a first input/output (I/O) circuit and a leakage detection circuit coupled to the first I/O circuit. In a test mode of operation, the leakage detection circuit tests the first I/O circuit for excessive leakage current. According to another embodiment, the integrated circuit also includes a first resistor coupled between a line voltage and the first I/O circuit and a second resistor coupled between the first I/O circuit and ground. Further, the integrated circuit includes a second I/O circuit coupled to the leakage detection circuit and the first and second resistors. The leakage circuit also tests the second I/O circuit for excessive leakage current in the test mode of operation.

Abstract: An apparatus for generating a pulse clock signal for a multiple-stage synchronizer provides a pulse clock signal to a synchronizer. The synchronizer synchronizes data received in a first clock domain, which is referenced to a first clock signal, to a second clock domain, which is referenced to a second clock signal. The apparatus includes a synchronization pulse generator and a multiplexer. The synchronization pulse generator generates a synchronization pulse based on the first clock signal and the second clock signal. The multiplexer outputs one of either the first clock signal or the synchronization pulse as the pulse clock signal based on an input control signal.