LTC3851A-1 Datasheet | Linear Technology

Features n Wide VIN Range: 4V to 38V Operation n RSENSE or DCR Current Sensing n ±1% Output Voltage Accuracy n Power Good Output Voltage Monitor 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 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 or 3mm × 3mm QFN Package Applications n Automotive Systems n Tele Systems n Industrial Equipment n Distributed DC Power Systems LTC3851A-1 Synchronous Step-Down Switching Regulator Controller Description The LTC®3851A-1 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-1 Features a precision 0.8V reference and a power good indicator. A wide 4V to 38V (40V absolute maximum) input supply range enpasses most battery configurations and intermediate bus voltages. The TK/SS pin ramps the output voltage during start‑up and shutdown with coincident or ratiometric tracking. Current foldback limits MOSFET heat dissipation during shortcircuit 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-1 contains an improved PLL pared to the LTC3851-1. The LTC3851A-1 is identical to the LTC3851A except that the ILIM pin is replaced by PGOOD. L, LT, LTC, LTM, Burst Mode, OPTI-LOOP, Linear...