More definitions

• Propagation delay: The delay through a gate

  • Measured at the 50% points on the input and output waveforms
  • Has a range: min/typical/max
  • Depends on the fanout
    • The number of loads the gate drives
  • Your design must work over the entire delay range

• Rise and fall times: Time for a signal to transition

  • Typically measured at 10% to 90% of the logic swing
    • Sometimes at 20% to 80%

• Pulse width — time that an output stays high

  • Duty cycle ? (pulse width) ? (pulse period)
  • Frequency ? 1 / period

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