Gray code counter is a digital counter that counts such that each successive bit patterns differs by only one bit. Unlike normal counters, there are no glitches in the count pattern (0 -> 1 -> 3 -> 2 -> 6 -> 7 ......... ). Since switching is less in gray code counters (i.e., exactly one-bit switches in one clock cycle), the power consumption of the gray code counter is significantly less compared to the normal counter.
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