LTC3868

FEATURES n Low Operating IQ: 170µA (One Channel On) n Wide Output Voltage Range: 0.8V ≤ VOUT ≤ 14V n Wide VIN Range: 4V to 24V n RSENSE or DCR Current Sensing n Out-of-Phase Controllers Reduce Required Input Capacitance and Power Supply Induced Noise n OPTI-LOOP® Compensation Minimizes COUT n Phase-Lockable Frequency (75kHz to 850kHz) n Programmable Fixed Frequency (50kHz to 900kHz) n Selectable Continuous, Pulse-Skipping or Burst Mode® Operation at Light Loads n Very Low Dropout Operation: 99% Duty Cycle n Adjustable Output Voltage Soft-Start n Power Good Output Voltage Monitor n Output Overvoltage Protection n Output Latchoff Protection During Short Circuit n Low Shutdown IQ: 8µA n Internal LDO Powers Gate Drive from VIN or EXTVCC n No Current Foldback During Start-Up n Small 5mm × 5mm QFN Package APPLICATIONS n Notebook and Palmtop Computers n Portable Instruments n Battery Operated Digital Devices n Distributed DC Power Systems LTC3868 Low IQ, Dual 2-Phase Synchronous Step-Down Controller DESCRIPTION The LTC®3868 is a high performance dual step-down switching regulator controller that drives all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows a phase-lockable frequency of up to 850kHz. Power loss and noise due to the input capacitor ESR are minimized by operating the two controller outputs out of phase. The 170μA no-load quiescent current extends operating life in battery-powered systems. OPTI-LOOP compensation allows the ...