Counters

Counters are important sequential circuits and find wide application. As an example, Figure 183 shows a hex counter, one that is designed to count in the sequence

$\begin{displaymath}0 \to 1 \to 2 \to 3 \to 4 \to 5 \to 0 \to 1 \to \ldots \end{displaymath}$

The timing waveform is shown in Figure 184.

**Figure 183:** Hex counter. The count is reflected in the 3-bit word Q₂Q₁Q₀.
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**Figure 184:** Hex counter timing. Note the count sequence Q₂Q₁Q₀.
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