The LM3881MM is a simple Power Sequencer with programmable time delay. The power sequencer offers the easiest method to control power-up and power-down of multiple power supplies (switching or linear regulators). By staggering the start-up sequence, it is possible to avoid latch conditions or large inrush currents that can affect the reliability of the system. The simple sequencer contains a precision enable pin and three open-drain output flags. When the LM3881 is enabled, the three output flags will sequentially release, after individual time delays, thus permitting the connected power supplies to start-up. The output flags will follow a reverse sequence during power-down to avoid latch conditions. Time delays are defined using an external capacitor and the output flag states can be inverted by the user.
Easiest method to sequence rails
Power-up and power-down control
Tiny footprint
Output invert feature
Timing controlled by small value external capacitor
