# Each flip-flop in a 4-bit ripple counter introduces a maximum delay of 40 n sec. The maximum clock frequency

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Each flip-flop in a 4-bit ripple counter introduces a maximum delay of 40 n sec. The maximum clock frequency is (a) 2.65 MHz (b) 6.25 MHz (c) 5.26 MHz (d) 6.52 MHz

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Each flip-flop in a 4-bit ripple counter introduces a maximum delay of 40 ns. The maximum clock frequency is 6.25MHz.

nff  Tdelay = 4*40 =160ns

so, max. frequency = 1/ (200*10-9 ) = 6.25MHz

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