ZHCSMX3C December 2020 – February 2023 LM5149-Q1
PRODUCTION DATA
#SNVSB29625 shows the schematic diagram of a dual-phase synchronous buck regulator with an output voltage of 3.3 V and a rated load current of 20 A. In this example, the target half-load and full-load efficiencies are 95% and 92%, respectively, based on a nominal input voltage of 12 V that ranges from 4 V to 72 V. The switching frequency is set at 400 kHz by resistors RRT1 and RRT2.
A design with 3 or more phases is feasible when appropriately phase-shifted clock signals are available. For example, a 4-phase design requires 4 LM5149-Q1 controllers with 0°, 90° and 270° external SYNC signals to achieve the ideal phase separation of 360° divided by the total number of phases.