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AN734
Vishay Siliconix
Design Guidelines for the Low-Noise Low-Dropout Regulator—Si9181
Nitin Kalje
INTRODUCTION
This application note discusses the operation and features of the Si9181, a 350-mA CMOS low-dropout (LDO), low-noise voltage regulator. Providing very low ground current to extend battery life, the Si9181 also offers superior line/load transient response and ripple rejection. Designed to maintain regulation while delivering currents from 0 mA to 600 mA, the Si9181 regulator also features an “out of regulation” error flag signal and ON/OFF control input for complete shutdown.
The Si9181 was designed for applications requiring a regulated voltage equal to or less than the voltage of the source or battery, and requiring very low output noise.