This table provides a comparison between the ON timings in the LTC2950 family. The first column, Turn On De-Bounce Time, represents the minimum length of time the push button must be held low before the enable goes high and turns on the system’s DC/DC converter. The LTC2951 and LTC2953 have fixed times, while the rest of the family has the option to use an external capacitor in order to extend the time beyond the default setting. The second column, System OK Response Time (or the blanking time), represents the maximum amount of time given to the system to power up. Once enable is asserted, the pushbutton and KILL input from the microprocessor is ignored. However, if KILL is not brought high during this time window, the enable output is released, causing a forced system shutdown.