The LM3880 simple power supply sequencer offers the easiest method to control power up sequencing and power down sequencing of multiple Independent voltage rails. By staggering the startup sequence, it is possible to avoid latch conditions or large in-rush currents that can affect the reliability of the system.
Available in a 6-pin SOT-23-6 package, the Simple Sequencer contains a precision enable pin and three open-drain output flags. The open-drain output flags permit that they can be pulled up to distinct voltage supplies separate from the sequencer VDD (so long as they do not exceed the recommended maximum voltage of 0.3V greater than VDD), so as to interface with ICs requiring a range of different enable signals. When the LM3880 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.
EPROM capability allows every delay and sequence to be fully adjustable. Contact Texas Instruments if a nonstandard configuration is required.
