You Have Two Counters Counting Upto 16, Built From Negedge Dff , Firs

1.	You Have Two Counters Counting Upto 16, Built From Negedge Dff , First Circuit Is Synchronous And Second Is "ripple" (cascading), Which Circuit Has A Less Propagation Delay? Why?
Answer» The synchronous counter will have LESSER delay as the input to each FLOP is readily available before the clock edge. Whereas the cascade counter will take long time as the output of one flop is used as clock to the other. So the delay will be PROPAGATING. For E.g.: 16 state counter = 4 bit counter = 4 Flip flops Let 10ns be the delay of each flop The worst case delay of RIPPLE counter = 10 * 4 = 40NS The delay of synchronous counter = 10ns only.(Delay of 1 flop) The synchronous counter will have lesser delay as the input to each flop is readily available before the clock edge. Whereas the cascade counter will take long time as the output of one flop is used as clock to the other. So the delay will be propagating. For E.g.: 16 state counter = 4 bit counter = 4 Flip flops Let 10ns be the delay of each flop The worst case delay of ripple counter = 10 * 4 = 40ns The delay of synchronous counter = 10ns only.(Delay of 1 flop)

You Have Two Counters Counting Upto 16, Built From Negedge Dff , First Circuit Is Synchronous And Second Is "ripple" (cascading), Which Circuit Has A Less Propagation Delay? Why?

Answer»

The synchronous counter will have LESSER delay as the input to each FLOP is readily available before the clock edge. Whereas the cascade counter will take long time as the output of one flop is used as clock to the other. So the delay will be PROPAGATING. For E.g.: 16 state counter = 4 bit counter = 4 Flip flops Let 10ns be the delay of each flop The worst case delay of RIPPLE counter = 10 * 4 = 40NS The delay of synchronous counter = 10ns only.(Delay of 1 flop)

The synchronous counter will have lesser delay as the input to each flop is readily available before the clock edge. Whereas the cascade counter will take long time as the output of one flop is used as clock to the other. So the delay will be propagating. For E.g.: 16 state counter = 4 bit counter = 4 Flip flops Let 10ns be the delay of each flop The worst case delay of ripple counter = 10 * 4 = 40ns The delay of synchronous counter = 10ns only.(Delay of 1 flop)

You Have Two Counters Counting Upto 16, Built From Negedge Dff , First Circuit Is Synchronous And Second Is "ripple" (cascading), Which Circuit Has A Less Propagation Delay? Why?

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