The TLV185x-Q1 and TLV186x-Q1 devices have an internal Power-on-Reset (POR) circuit for known start-up or power-down conditions. While the power supply (V+) is ramping up or ramping down, the POR circuitry will be activated for up to 2 ms after the V_POR of 1.5 V is crossed. When the supply voltage is equal to or greater than the minimum supply voltage, and after the delay period, the comparator output reflects the state of the differential input (V_ID).

For the TLV185x-Q1 push-pull output devices, the output is held low during the POR period (t_on).

For the TLV186x-Q1 open drain output devices, the POR circuit will keep the output high impedance (Hi-Z) during the POR period (t_on).

Figure 7-3 Power-On Reset Timing Diagram

Note that it the nature of an open collector output that the output will rise with the pull-up voltage during the POR period.