The TPS791 device is a low-dropout (LDO) low-power linear voltage regulator that features high power-supply rejection ratio (PSRR), ultralow noise, fast start-up, and excellent line and load transient responses in a small outline, SOT23 package. The device is stable, with a small 1-µF ceramic capacitor on the output. The TPS791 uses an advanced, proprietary BiCMOS fabrication process to yield extremely low dropout voltages (for example, 38 mV at 100 mA, TPS79147). This device achieves fast start-up times (approximately 63 µs with a 0.001-µF bypass capacitor) while consuming very low quiescent current (170 µA typical). Moreover, when the device is placed in standby mode, the supply current is reduced to less than 1 µA. The TPS79118 exhibits approximately 15 µVRMS of output voltage noise with a 0.1-µF bypass capacitor. Applications with analog components that are noise sensitive, such as portable RF electronics, benefit from the high PSRR and low noise features as well as the fast response time.