LM3355 Datasheet | National Semiconductor

Description The LM3355 is a CMOS switched capacitor DC/DC converter that produces a regulated output voltage by automatically stepping up (boost) or stepping down (buck) the input voltage. It accepts an input voltage between 2.5V and 5.5V. The LM3355 is available with a standard output voltage of 4.1V (ideal for white LED applications). If other output voltage options between 1.8V and 4.1V are desired for other applications, please contact your National Semiconductor representative. The LM3355’s proprietary buck-boost architecture enables up to 50 m A of load current at an average efficiency greater than 75%. Typical operating current is only 375 µA and the typical shutdown current is only 2.3 µA. The LM3355 is available in a 10-pin MSOP package. This package has a maximum height of only 1.1 mm. The high efficiency of the LM3355, low operating and shutdown currents, small package size, and the small size of the overall solution make this device ideal for battery powered, portable, and hand-held applications. See the LM3352 for up to 200m A of output current. Features n Regulated VOUT with ± 3% accuracy n Standard output voltage of 4.1V n Custom output voltages available from 1.8V to 4.1V in 100 m V increments n 2.5V to 5.5V input voltage n Up to 50 m A output current n > 75% average efficiency n Uses few, low-cost external ponents n Very small solution size n 375 µA typical operating current n 2.3 µA typical shutdown current n 1 MHz switching frequency (typical) n Architecture and control methods provide high load current and good efficiency n MSOP-10 package n Over-temperature protection Applications n White LED display backlights n 1-cell Lilon battery-operated equipment including PDAs, hand-held PCs, cellular phones n Flat panel displays n Hand-held instruments n Ni Cd, Ni MH, or alkaline battery powered systems Typical Operating Circuit DS200219-1 © 2001 National Semiconductor Corporation DS200219 .national. Connection Diagram DS200219-2 Top View...