LTC3499 Datasheet | Linear Technology

LTC3499/LTC3499B 750m A Synchronous Step-Up DC/DC Converters with Reverse-Battery Protection Features n Reverse-Battery Protection for DC/DC Converter and Load n High Efficiency: Up to 94% n Generates 5V at 175m A from a 1.8V Input n Operates from 1.8V to 5.5V Input Supply n 2V to 6V Adjustable Output Voltage n Inrush Current Controlled During Start-Up n Output Disconnnect in Shutdown n Low Noise 1.2MHz PWM Operation n Tiny External ponents n Automatic Burst Mode® Operation (LTC3499) n Continuous Switching at Light Loads (LTC3499B) n Overvoltage Protection n 8-Lead (3mm × 3mm × 0.75mm) DFN and MSOP Packages APPLICATIONS n Medical Equipment n Digital Cameras n MP3 Players n Handheld Instruments L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. DESCRIPTION The LTC®3499/LTC3499B are synchronous, fixed frequency step-up DC/DC power converters with integrated reverse battery protection that protect and disconnect the devices and load when the battery polarity is reversed while delivering high efficiency in a small (3mm × 3mm) DFN package. True output disconnect eliminates inrush current and allows zero load current in shutdown. The devices feature an input voltage range of 1.8V to 5.5V enabling operation from two alkaline or Ni MH batteries. The switching frequency is internally set at 1.2MHz allowing the use of tiny surface mount inductors and capacitors. A minimal number of external ponents are required to generate output voltages ranging from 2V to 6V. The LTC3499 Features automatic Burst Mode operation to increase efficiency at light loads, while the LTC3499B Features continuous switching at light loads. The soft-start time is externally programmable through a small capacitor. Anti-ring circuitry reduces EMI emissions by damping the inductor in discontinuous mode. The devices feature <1µA shutdown...