LP3917 Datasheet | National Semiconductor

Description LP3917 is a plete Power Management Unit designed for CDMA cellular phones. LP3917 PMU contains 9 low noise low dropout voltage regulators, 2 buck regulators, an USB Transceiver, two parators and a high speed serial interface to program on/off conditions and output voltages of individual regulators, and to read status information of the PMU. Buck regulators have an automatic switch to PFM mode at low load conditions allowing very good efficiency also at low output currents. LDO regulators provide very low noise, 35 u V typ, ideally suited for supplying voltage to RF section. Two parators can be used for detecting external accessories like ear plug etc. LP3917 can use interrupt for alerting BB processor of status changes instead of using inefficient status polling. Features - Two high efficiency Synchronous Magnetic Buck Regulators, IOUT 800 m A and 600 m A High efficiency PFM mode @ low IOUT Auto Mode PFM/PWM switch Low inductance 2.2 u H @ 2 MHz clock 9 Low Noise LDO's 3 x 300 m A 5 x 150 m A 1 x 80 m A SW controllable LDO outputs USB 2.0 patible Transceiver (12 Mbps) Thermal Shutdown with Early Warning Alarm Very low Sleep mode current Battery Voltage Monitor output Interrupt Request for reducing SW polling Ultra small 3.5x3.5 mm Micro SMDxt 49 bump package - - Key Specifications - - - - - 3.0V to 5.5V Input Voltage Range 170 m V typ Dropout Voltage on LDO's @ 300 m A 2% (typ) Output Voltage accuracy on LDO's 35 µV noise on LDO's 800/600 m A Buck regulators with 3% (typ) Accuracy and up to 90% efficiency - - - - - - - Applications - CDMA Handsets Please contact NSC Sales for a full datasheet for the device. System Diagram © 2006 National Semiconductor Corporation .national. Typical Application Diagram .national. Device Pin Diagram TOP VIEW Package Marking Information Ordering Information Startup Sequential Non-Sequential Sequential Sequential Non-Sequential Non-Sequential HF_PWR...