The LP3984 is designed for portable and wireless applications with demanding performance and space requirements. The LP3984's performance is optimized for battery powered systems to deliver extremely low dropout voltage and low quiescent current. Regulator ground current increases only slightly in dropout, further prolonging the battery life. Power supply rejection is better than 60 dB at low frequencies and starts to roll off at 10 kHz. High power supply rejection is maintained down to lower input voltage levels common to battery operated circuits. The device is ideal for mobile phone and similar battery powered wireless applications. It provides up to 150 mA, from a 2.5V to 6V input, consuming less than 1.2A in disable mode and has fast turn-on time less than 20s. The LP3984 is available in micro SMD and 5 pin SOT-23 package. Performance is specified for -40C to +125C temperature range and is available in 1.5V, 1.8V, 2.0V, and 3.1V output voltages. For other output voltage options from 1.5V to 3.5V, please contact National Semiconductor sales office.