The overdrive voltage, VOD, is the amount of input voltage beyond the reference voltage (and not the total input peak-to-peak voltage). The overdrive voltage is 100mV as shown in the Figure 8-1 example. The overdrive voltage can influence the propagation delay (tp). The smaller the overdrive voltage, the longer the propagation delay, particularly when <100mV. If the fastest speeds are desired, it is recommended to apply the highest amount of overdrive possible.
The risetime (tr) and falltime (tf) is the time from the 20% and 80% points of the output waveform.