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Codiode/Problems/Sequential Logic

Clock Multiplexer Without Synchronization

MediumLogic CircuitDebug

A glitch-free clock multiplexer safely switches a single output clock between two asynchronous clock sources without generating runt pulses.

Expected behavior:

When Select is 0, ClkOut follows Clk0. When Select is 1, ClkOut follows Clk1. The transition between clocks must be clean and stable.

Simulation reports metastability warnings on the clock-gating latches when Select toggles asynchronously. The ClkOut signal occasionally propagates an undefined state during the clock switch. Inspect the circuit and correct the fault.

Constraints

  • Do not remove the feedback paths between the two clock selection branches.
  • You must use standard D flip-flops for synchronization.
  • The output must remain glitch-free during any asynchronous transition of the select signal.

Topics

CDCSynchronizerClock Multiplexer

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Place the gates, wire them up and watch the signals settle. Every submission runs on the same simulation engine that grades it.

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