LTC3670

LTC3670 Monolithic 400mA Buck Regulator with Dual 150mA LDOs in 3mm × 2mm DFN FEATURES DESCRIPTION n Triple Output Supply from a Single 2.5V to 5.5V Input n 400mA Buck DC/DC Plus Dual 150mA LDOs in One IC n Outputs Regulate Down to 0.8V n ±2.5% Reference Accuracy n Constant-Frequency 2.25MHz Operation n Burst Mode® Operation for High Efficiency at Light Loads; IQ = 70µA, All Outputs Enabled n Independent Enable Pin for Each Output n Current Mode Operation for Excellent Line and Load Transient Response n Internal Soft-Start for Each Output n Tiny 12-Lead 3mm × 2mm × 0.75mm DFN Package APPLICATIONS n Handheld Products n Portable Instruments n Single-Cell Li-Ion/Li-Polymer Powered Devices n DMB/DVB-H Multimedia Cell Phones n Multivoltage Power for Digital Logic, I/O, FPGAs, CPLDs, ASICs, SoCs, CPUs and RF Chipsets The LTC®3670 is a triple power supply composed of a 400mA synchronous buck regulator and two 150mA low dropout linear regulators (LDOs). The input supply range of 2.5V to 5.5V is especially well-suited for single-cell Lithium-Ion and Lithium-Ion/Polymer applications, and for powering low voltage ASICs and SoCs from 3V, 3.3V or 5V rails. Regulated output voltages are programmed via external resistors. Each output has its own enable pin for maximum flexibility. The 400mA buck regulator features constant-frequency 2.25MHz operation, allowing small surface mount inductors and capacitors to be used. Burst Mode operation maintains high efficiency in light...