LTC3523-2

LTC3523/LTC3523-2 Synchronous 600mA Step-Up and 400mA Step-Down DC/DC Converters FEATURES DESCRIPTION n Dual High Efficiency DC/DC Converters: Step-Up (VOUT = 1.8V to 5.25V, ISW = 600mA) Step-Down (VOUT = 0.615V to 5.5V, IOUT = 400mA) n 1.8V to 5.5V Input Voltage Range n Up to 94% Efficiency n Pin Selectable Burst Mode® Operation n 45μA Quiescent Current in Burst Mode Operation n 1.2MHz (LTC3523) or 2.4MHz (LTC3523-2) Switching Frequency n Independent Power Good Indicator Outputs n Integrated Soft-Start n Thermal and Overcurrent Protection n <3μA Quiescent Current in Shutdown n Small 16-Lead 3mm × 3mm × 0.75mm QFN Package APPLICATIONS n Digital Cameras n Medical Instruments n Industrial Handhelds n GPS Navigators The LTC®3523/LTC3523-2 combine a 600mA step-up DC/DC converter with a 400mA synchronous step-down DC/DC converter in a tiny 3mm × 3mm package. The 1.2MHz/2.4MHz switching frequencies minimize the solution footprint while maintaining high efficiency. Both converters feature soft-start and internal compensation, simplifying the design. Both the step-up and step-down converters are current mode controlled and utilize an internal synchronous rectifier for high efficiency. The step-up supports 0% duty cycle operation and the step-down converter supports 100% duty cycle operation to extend battery run time. If the MODE pin is held high, both converters automatically transition between Burst Mode operation and PWM operation improving light load efficiency. Fixed, low noise 1...