LTC3770 Datasheet | Linear Technology

Features n Wide VIN Range: 4V to 32V n ±0.67% 0.6V Reference Voltage n Output Voltage Tracking Capability n Programmable Margining n Sense Resistor Optional n True Current Mode Control n 2% to 90% Duty Cycle at 200k Hz n t ON(MIN) ≤ 100ns n Phase-Locked Loop Frequency Synchronization n Powerful Dual N-Channel MOSFET Driver n Adjustable Cycle-by-Cycle Current Limit n Adjustable Switching Frequency n Programmable Soft-Start n Current Foldback Protection (Disabled at Start-Up) n Output Overvoltage Protection n Micropower Shutdown: IQ < 30μA n Power Good Output Voltage Monitor Tracks the Reference Input Pin n Available in (5mm × 5mm) QFN and 28-Lead SSOP Packages APPLICATIONS n Distributed Power Systems n Server Power Supply Fast No RSENSETM Step-Down Synchronous Controller with Margining, Tracking and PLL DESCRIPTION The LTC®3770 is a synchronous step-down switching regulator controller with output voltage up/down tracking capability and voltage margining. Its advanced functions and high accuracy reference are ideal for powering high performance server, ASIC and puter memory systems. The LTC3770 uses a constant on-time, valley current mode control architecture to deliver very low duty factors without requiring a sense resistor. The operating frequency is selected by an external resistor and is pensated for variations in input supply voltage. An internal phase-locked loop allows the IC to be synchronized to an external clock. Fault protection is provided by an overvoltage parator and input undervoltage lockout. The regulator current limit is user programmable. A wide supply range allows voltages as high as 32V to be stepped down to as low as a 0.6V output. Power supply sequencing is acplished using an external soft-start timing capacitor. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. RSENSE is a registered trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners....