LTC3851 Datasheet | Linear Technology

Features n Wide VIN Range: 4V to 38V Operation n RSENSE or DCR Current Sensing n ±1% Output Voltage Accuracy n Phase-Lockable Fixed Frequency: 250k Hz to 750k Hz n Dual N-Channel MOSFET Synchronous Drive n Very Low Dropout Operation: 99% Duty Cycle n Adjustable Output Voltage Soft-Start or Tracking n Output Current Foldback Limiting n Output Overvoltage Protection n 5V Internal Regulator n OPTI-LOOP® pensation Minimizes COUT n Selectable Continuous, Pulse-Skipping or Burst Mode® Operation at Light Loads n Low Shutdown IQ: 20μA n VOUT Range: 0.8V to 5.5V n Thermally Enhanced 16-Lead MSOP, 16-Lead Narrow SSOP or 3mm × 3mm QFN Package APPLICATIONS n Automotive Systems n Tele Systems n Industrial Equipment n Distributed DC Power Systems Synchronous Step-Down Switching Regulator Controller DESCRIPTION The LTC®3851 is a high performance synchronous step-down switching regulator controller that drives an all N-channel synchronous power MOSFET stage. A constant frequency current mode architecture allows a phase-lockable frequency of up to 750k Hz. OPTI-LOOP pensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3851 Features a precision 0.8V reference that is patible with a wide 4V to 38V input supply range. The TK/SS pin ramps the output voltage during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions. The MODE/PLLIN pin selects among Burst Mode operation, pulse skipping mode or continuous inductor current mode at light loads and allows the IC to be synchronized to an external clock. The LTC3851-1 is a version with a power good output signal instead of adjustable current limit. L, LT, LTC, LTM, Burst Mode and OPTI-LOOP are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5408150, 5481178, 5705919, 5929620, 6304066, 6498466, 6580258,...