74ACT11478
description
The 74ACT11478 is an 8-bit dual-rank synchronizer circuit designed specifically for data synchronization applications where the normal setup and hold time specifications are frequently violated.
Synchronization of two digital signals operating at different frequencies is a mon system problem. This problem is typically solved by synchronizing one of the signals to the local clock through a flip-flop. This solution, however, causes the setup and hold time specifications associated with the flip-flop to be violated. When the setup or hold time specification is violated, the output response is uncertain.
A flip-flop is metastable if its output hangs up in the region between VIL and VIH. The metastable condition lasts until the flip-flop recovers into one of its two stable states. With conventional flip-flops, this recovery time can be longer than the specified maximum propagation delay.
The problem of metastability is typically solved by adding an additional layer of...
