| 摘要 |
A self-calibrating strobe signal generator for a BIST circuit responds to an edge of an input strobe signal by generating corresponding edges of first and second strobe signals separated in time by a target delay specified by input data. The strobe signal generator includes a multiplexer, a delay circuit and a controller. The multiplexer normally provides the input strobe signal as a multiplexer output signal to the delay circuit which generates edges in each of the first and second strobe signals in response to each edge in the multiplexer output signal with a programmable delay between corresponding first and second strobe signal edges. During a calibration process the control circuit adjusts the programmable delay by counting cycles of a reference clock signal occurring during a predetermined number of cycles of the multiplexer output signal when the multiplexer is set to select the first strobe signal and then the second strobe signal as the source of the multiplexer output signal such that the multiplexer output signal oscillates, and by incrementing or decrementing the programmable delay depending on whether a difference between the counts matches the input data.
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