Logic circuits

In a combinational circuit, what is the unwanted pulse that appears briefly at the output when an input changes, due to different delays along different paths?

  1. AMetastability
  2. BGlitch (hazard)
  3. CLatch-up
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Answer: B. Glitch (hazard)

When the same input change reaches the output through paths with different delays, the output may briefly take a wrong value. This is called a glitch (hazard). In a synchronous circuit it is not a problem as long as the output settles before the clock edge, but it wastes power.

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