LP3986 Datasheet | National Semiconductor

Description The LP3986 is a 150 m A dual low dropout regulator designed for portable and wireless applications with demanding performance and board space requirements. The LP3986 is stable with a small 1 µF ± 30% ceramic output capacitor requiring smallest possible board space. The LP3986’s performance is optimized for battery powered systems to deliver ultra low noise, extremely low dropout voltage and low quiescent current independent of load current. Regulator ground current increases very slightly in dropout, further prolonging the battery life. Optional external bypass capacitor reduces the output noise further without slowing down the load transient response. Fast start-up time is achieved by utilizing a speed-up circuit that actively precharges the bypass capacitor. Power supply rejection is better than 60 d B at low frequencies and 55 d B at 10 k Hz. High power supply rejection is maintained at low input voltage levels mon to battery operated circuits. The LP3986 is available in a micro SMD package. Performance is specified for a - 40˚C to +125˚C temperature range. For single LDO applications, please refer to the LP3985 datasheet. Features n Miniature 8-I/O micro SMD package n Stable with 1µF ceramic and high quality tantalum output capacitors n Fast turn-on n Two independent regulators n Logic controlled enable n Over current and thermal protection Key Specifications n Guaranteed 150 m A output current per regulator n 1n A typical quiescent current when both regulators in shutdown mode n 60 m V typical dropout voltage at 150 m A output current n 115 µA typical ground current n 40 µV typical output noise n 200 µs fast turn-on circuit n - 40˚C to +125˚C junction temperature Applications n n n n CDMA cellular handsets GSM cellular handsets Portable information appliances Portable battery applications Typical Application Circuit © 2003 National Semiconductor Corporation DS200034 .national. Block Diagram Pin Description Name...