Don Jones
National Semiconductor

Typical low-dropout (LDO) linear voltage regulators do not provide a method of limiting the in-rush current during start up conditions. Using the LP38851, LP38852, and LP38853 adjustable LDO linear regulators, with nominal current levels of 800mA, 1.5A, and 3A, respectively, will eliminate this problem by including user-programmable, soft-start circuitry with the device. This paper explains how National Semiconductor's LP38851/52/53 devices, with soft-start, provide a reliable way to ensure that start-up into high capacitive loads is uneventful and stress free.