摘要 |
An input circuit is provided for coupling to a source-synchronous multi-level bus carrying data, clock, and complementary clock signals. The clock and complementary clock signals have a less than full voltage swing than the data signal so they can act as reference voltages for the data signal. The circuit includes a first differential receiver having inputs coupled to the data and the clock signals, a second differential receiver having inputs coupled to the data signal and a reference signal, and a third differential receiver having inputs coupled to the data and the complementary clock signals. The circuit further includes first, second, and third flip-flops having data inputs coupled to outputs of the first, the second, and the third differential receivers, and clock inputs coupled to a delayed clock signal generated from the clock and the complementary clock signals. The outputs of the flip-flops determine the level of the data signal.
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