Demonstration Circuit 2455A-B features PolyPhase® design using three LTM4650EY-1 (B-grade high efficiency, high density, dual 25A, switch mode step-down power module regulators. The input voltage is from 4.5V to 15V. The output voltage is jumper selectable from 0.9V to 1.8V. DC2455A-B can deliver nominal 150A output current. As explained in the data sheet, output current de-rating is necessary for certain VIN , VOUT , and thermal conditions. DC2455A-B always operates in continuous conduction mode.
The switching frequency can be programmed through a resistor or can be synchronized to an external clock signal. The board allows the user to program how its output voltage ramps up and down through the TRACK pin. The output voltage is tightly regulated between test points “VO+ ” and “VO– ” through remote output voltage sensing, which improves output voltage regulation at heavy loads. These features and the availability of the LTM4650EY-1 in a compact 16mm × 16mm × 5.01mm BGA package make it ideal for use in many high-density point-of-load regulation applications. The LTM4650-1 data sheet must be read in conjunction with this demo manual for working on or modifying the demo circuit DC2455A-B.