A constant-frequency current mode architecture allows a selectable fixed or phase-lockable (PLL) frequency from 250kHz to 750kHz. Power loss and supply noise are minimized by operating the three stages 120° out-of-phase. The LTC3853 can also be used in a 2+1 configuration, with output stages 1 and 3 180° out-of-phase with output stage 2. OPTI-LOOP® compensation allows for a wide range of output capacitance and ESR values, including all ceramic input and output capacitors. The LTC3853 can be configured for coincident or ratiometric tracking for safe power-up and power-down of voltage sensitive ASIC’s and FPGA’s.

