LT1129-3.3

The LT1129/LT1129-3.3/LT1129-5 are micropower low dropout regulators with shutdown. The devices are ca-pable of supplying 700mA of output current with a drop-out voltage of 0.4V at maximum output. Designed for use in battery-powered systems the low quiescent current,50µA operating and 16µA in shutdown, make them an ideal choice. The quiescent current does not rise in dropout as it does with many other low dropout PNP regulators.

Other features of the LT1129 /LT1129-3.3/LT1129-5 in-clude the ability to operate with small output capacitors.They are stable with only 3.3µF on the output while most older devices require between 10µF and 100µF for stabil-ity. Also the input may be connected to ground or a reverse voltage without reverse current flow from output to input.This makes the LT1129/LT1129-3.3/LT1129-5 ideal for backup power situations where the output is held high and the input is at ground or reversed. Under these conditions,only 16µA will flow from the output pin to ground. The devices are available in 5-lead TO-220, 5-lead DD, and 3-lead SOT-223 packages.