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What is flip-flop delay?
A D (or Delay) Flip Flop (Figure 1) is a digital electronic circuit used to delay the change of state of its output signal (Q) until the next rising edge of a clock timing input signal occurs.
What contributes to propagation delay?
Factors that affect propagation delay are: the way it is measured, the amount of overdrive, the supply voltage, the output driver supply voltage, capacitive loading, the common mode voltage, the configuration (inverting or non-inverting), the edge on which one measures (rising or falling) and temperature.
Why do flip flops have a longer propagation delay?
The further apart those two Flip-Flops are or the more combinational logic in the middle, the longer the propagation delay between the two of them. The longer the propagation delay, the slower your clock is able to run. The reason for this is that both Flip-Flops use the same clock. The first Flip-Flop drives its output at clock edge 1.
Why do flip flops use the same clock?
The further apart those two Flip-Flops are or the more combinational logic in the middle, the longer the propagation delay between the two of them. The longer the propagation delay, the slower your clock is able to run. The reason for this is that both Flip-Flops use the same clock.
How long does it take for a flip flop to travel?
The amount of time it takes for the output of the first Flip-Flop to travel to the input of the second Flip-Flop is the Propagation Delay. The further apart those two Flip-Flops are or the more combinational logic in the middle, the longer the propagation delay between the two of them.
How does the propagation delay affect the clock?
The longer the propagation delay, the slower your clock is able to run. The reason for this is that both Flip-Flops use the same clock. The first Flip-Flop drives its output at clock edge 1. The second Flip-Flop does not see the change on the output of the first Flip-Flop until clock edge 2, at which point it drives its output.