What are metastable materials?

Metastable materials, or materials that transform to another state over a long period of time, are ubiquitous in both nature and technology and often have superior properties. Chocolate, for example, is metastable, with a lower melting point and better texture than stable chocolate.

What are examples of metastable?

A ball resting in a hollow on a slope is a simple example of metastability. If the ball is only slightly pushed, it will settle back into its hollow, but a stronger push may start the ball rolling down the slope. Bowling pins show similar metastability by either merely wobbling for a moment or tipping over completely.

What do you mean by metastable?

metastable. / (ˌmɛtəˈsteɪbəl) physics / adjective. (of a body or system) having a state of apparent equilibrium although capable of changing to a more stable state. (of an atom, molecule, ion, or atomic nucleus) existing in an excited state with a relatively long lifetime.

What is the difference between stable and metastable?

The key difference between stable and metastable is that the term stable refers to the state of a material being truly unchanging whereas the term metastable refers to the state of a material where a change cannot be observed because the changing is too slow to be observed.

Which is an example of a case of metastability?

A common example is the case of data violating the setup and hold specifications of a latch or a flip-flop. In an ideal world, where all logic designs are synchronous and all inputs are tied to the system clock, metastability would not be a concern because all timing conditions for the flip-flops would be met.

Is the metastability of the F / F always stable?

This extra time is called the metastable resolution time. However, metastability may not always result in unpredictable output. If provided sufficient time with proper excitation, the f/f can infact settle to a stable state. But in the post GHz designs, time is at a premium, so the occurrence of the metastability itself has to be taken care of.

Why is metastability not a problem in a synchronous World?

In an ideal world, where all logic designs are synchronous and all inputs are tied to the system clock, metastability would not be a concern because all timing conditions for the flip-flops would be met.

How is the exponential term related to metastability?

The exponential term in the equation describes the probability that a metastable condition will last for time t’. As one increases time t’ that one waits before looking at a f/f’s output, the likelihood of seeing unresolved metastability is exponentially decreased.