The overdrive voltage, V_OD, 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 5-1 example. Similarly, underdrive voltage, V_UD, is how far below REF the input starts. The overdrive and underdrive voltages influence the propagation delay (t_p). See curves in the Typical Characteristics section for more details. The smaller the overdrive voltage, the longer the propagation delay, particularly when <100mV. If the fastest speeds are desired, apply the highest amount of overdrive possible. Contrary to overdrive voltage, larger underdrive voltage causes propagation delay to increase. This is particularly important in applications where rail-to-rail input swings are present at the comparator inputs. The result can be skewed propagation delay (difference between tp_LH and tp_HL). As a low power comparator, do not use this comparator family if variation in propagation delay is critical.

The risetime (t_r) and falltime (t_f) is the time from the 20% and 80% points of the output waveform.