| 摘要 |
<p>An apparatus to overcome a metastable state in a communication system employing a common clock period includes first and second latches, the first latch being clocked by a clock signal and the second latch being clocked by an inverted version of said clock signal, each of the first and second latches receiving a data stream. A delay device delays the output of the second latch by one half of a cycle of the clock signal. A multiplexer outputs the output of the first latch when the received data stream does not exhibit metastability relative to the clock signal and outputs the output of the delay device in the presence of metastability. By latching the data according to the inverted clock, the data is not latched during state transitions thereof and metastability is avoided. The delay device re-synchronizes the latched data with the active edges of the clock signal.</p> |
