At DVCon’16, Mark Litterick presented a paper and presentation on “Full Flow Clock Domain Crossing – From Source to Si.” Here is the abstract for the paper:
Functional verification of clock domain crossing (CDC) signals is normally concluded on a register-transfer level (RTL) representation of the design. However, physical design implementation during the back-end pre-silicon stages of the flow, which turns the RTL into an optimized gate-level representation, can interfere with synchronizer operation or compromise the effectiveness of the synchronizers by eroding the mean time between failures (MTBF). This paper aims to enhance cross-discipline awareness by providing a comprehensive explanation of the problems that can arise in the physical implementation stages including a detailed analysis of timing intent for common synchronizer circuits.
Mark works for Verilab as senior verification consultant and holds the position of fellow. He is based in Munich, Germany. To see more of Mark’s technical papers, check out his profile page on the Verilab web-site.
Even though, you may have signed-off for CDC at RTL, logic synthesis, design-for-test and low-power optimization tools can break CDC at the gate-level, the physical implementation stage of design. Real Intent’s Meridian products provide clock-domain crossing verification and sign-off. Our most recent offering is Meridian Physical CDC and provides sign-off at the netlist level of the design. It uses a mix of structural and formal methods to identify glitching and other errors that break the correct registration of signals crossing clock domains. (more…)