采样频率越快,采到在setup time和hold time之间信号的可能性越高,平均失效时间越短,在某个时间内亚稳态频率越快 MTBF - 数值非常大,说明两次亚稳态之间的时间非常长,认为不发生亚稳态 使用三个寄存器处理1bit信号 时钟信号高的时候,可以使用三个寄存器(同步器)处理 4.3 Synchronizer effect - latency uncertainty...
5.亚稳态与系统可靠性 使用同步电路以后，亚稳态仍然有发生的可能，与此相连的是平均故障间隔时间MTBF（mean time between failure），亚稳态的发生概率与时钟频率无关，但是 MTBF与时钟有密切关系。 有文章提供了一个例子，某一系统在 20MHz 时钟下工作时，MTBF约为 50年，但是时钟频率提高到 40MHz...
使用同步电路以后,亚稳态仍然有发生的可能,与此相连的是MTBF(Mean Time Between Failure),亚稳态的发生概率与时钟频率无关,但是MTBF与时钟有密切关系。有文章提供了一个例子,某一系统在20MHz时钟下工作时,MTBF约为50年,但是时钟频率提高到40MHz时,MTBF只有1分钟!可见降低时钟频率可以大大减小亚稳态导致系统错误的...
我果竟然在面试里会问metastability是怎么算的,号称自己的design会跑simulation,有signoff criteria。(我觉得他真的是吹tmd牛逼) anyway: S:是设计的 等待信号稳定的时间,时间越长MTBF指数级增大。所以高频电路2sync不够要用3sync来保证 τ : 是电路本身RC相关值。和给电容充电相似 W: 一个周期中会引起亚稳态...
I am not looking here to derive MTBF equation :-) So how do I avoid metastability? In reality, one cannot avoid metastability and increased clock-to-Q delays in synchronizing asynchronous inputs, without the use of tricky self-timed circuits. So a more appropriate question might be "How do...
The power supply disturbance and temperature variation effects on the metastability were also measured, and the data show that a 0.75-V change of power supply voltage and 75 degrees C change of chip temperature cause a four orders of magnitude difference in the MTBF. The simulation results using...
A webinar presented Last week introduced two free aids to evaluating synchronizer Mean Time Between Failures (MTBF). The first,MetaACE LTD,is used to characterize the intrinsic parameters needed to calculate MTBF (tau and Tw). This limited version ofMetaACEsupports up to 250 circuit nodes, which...
The evaluation of the MTBF (Mean Time Between Failure) characteristics of PLD is done, based on the propagation delay distribution measurement of bistable output in the circumstances of deliberately inducing metastable behaviour. The testing results help in design, examine and to predict required MTBF...
Exorcise metastability from your design. (includes related articles on manager knowledge of metastability, characterizing metastability and hw to estimate mean time between failure (MTBF)) (Tutorial)Shear, David
As you mention, if the slack is negative there is no MTBF, as it will always fail. Anyway, the asynchronous path and the synchronizer should be two separate things. Out of curiosity, how do you like the MTBF analysis? I don't see this used very much although think it's a very ...