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Codiode/Problems/Sequential Logic

Ripple Down-Counter Waveform Trace

MediumLogic CircuitTiming Diagram

A 4-bit ripple down-counter is constructed from four T flip-flops where Q0 toggles on every positive edge of CLK, and each subsequent stage toggles on the positive edge (LOW-to-HIGH transition) of the previous stage's output.

Five signals are shown: CLK (clock, period 2), and four outputs Q0, Q1, Q2, and Q3 (initially all 1, representing the decimal value 15).

Trace Q0, Q1, Q2, and Q3 across all 32 time steps to reveal the full down-count sequence and the final rollover back to 15.

Constraints

  • Each flip-flop is positive-edge-triggered.
  • A stage only changes state when its specific trigger condition is met.
  • All initial output values are 1 at time step 0.

Topics

timingsequential-logicflip-flopscounters

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