View rt9193 datasheet:

® RT9193 300mA, Ultra-Low Noise, Ultra-Fast CMOS LDO Regulator General Description Features Ultra Low Noise for RF Application The RT9193 is designed for portable RF and wireless Ultra Fast Response in Line/Load Transient applications with demanding performance and space Quick Start-Up (Typically 50µ µ µs) µ µ requirements. The RT9193 performance is optimized for <0.01µ µ µA Standby Current When Shutdown µ µ battery-powered systems to deliver ultra low noise and Low Dropout : 220mV @ 300mA low quiescent current. A noise bypass pin is available for Wide Operating Voltage Ranges : 2.5V to 5.5V further reduction of output noise. Regulator ground current TTL-Logic-Controlled Shutdown Input