LTC3851A 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 LTC3851A Synchronous Step-Down Switching Regulator Controller Description The LTC®3851A 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 LTC3851A 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 LTC3851A contains an improved PLL pared to the LTC3851. The LTC3851A-1 is a version with a power good output signal instead of adjustable current limit. L, LT, LTC, LTM, Burst Mode, OPTI-LOOP, Linear Technology and the Linear logo are registered trademarks and No RSENSE, Ultra Fast are trademarks of Linear Technology Corporation. All other...