DC/DC Controller Operates With Power Blocks And DrMOS

Linear Technology Corp. has introduced the LTC3861, a dual output synchronous step-down DC/DC controller with multiphase operation, differential output voltage sensing and high frequency operation. This controller works in conjunction with external power train devices such as power blocks and DrMOS, as well as discrete N-channel MOSFETs and associated gate drivers, enabling flexible design configurations. Up to 12 phases can be paralleled and clocked out-of-phase to minimize input and output filtering for very high current requirements (up to 300A). The devices operates with a VCC voltage ranging from 3 V to 5.5 V, a VIN voltage from 3V to 24V; it produces output voltages from 0.6 V to 5 V. The output current is sensed by monitoring the voltage drop across the output inductor (DCR) for maximum efficiency or using a sense resistor. Its adjustable current limit can be configured for very low sense voltages (up to 50 mV) to minimize power loss. Applications include high current power distribution and industrial systems, DSP and ASIC supplies.