See Also

In a design, the data bits that are transferred between asynchronous clock domains should be synchronized according to one of the following sets of guidelines

If the data bits belong to single-bit data, the synchronization of the data bits should follow the following guidelines to avoid metastability problems:

• Each data bit should be synchronized with two cascading registers in the receiving asynchronous clock domain.

• The cascading registers should be triggered on the same clock edge.

• There should be no logic between the output of the transmitting clock domain and the cascaded registers in the receiving asynchronous clock domain.

If the data bits belong to multi-bit data, the synchronization of the data bits should follow the following guidelines to avoid metastability problems:

• Only the data bits that act as REQ (Request) and/or ACK (Acknowledge) signals should be synchronized.

• The data bits that act as REQ and ACK signals should be synchronized with two or more cascading registers in the receiving asynchronous clock domain.

• The cascading registers should be triggered on the same clock edge.

• There should be no logic between the output of the transmitting clock domain and the cascaded registers in the receiving asynchronous clock domain.

Back to Top