3 A buck-boost regulator with synchronous rectification
The LTC3113EDHD#PBF: This is a single-inductor buck-boost converter delivering 3 A continuous output. The topology regulates the output voltage above, below, or equal to the input — useful for battery-powered systems where the cell voltage drops below the regulated rail. The synchronous rectifier (internal low-side FET) replaces the external catch diode typical in non-synchronous designs, reducing the conduction loss and component count. Efficiency benefits most at lower output voltages where the diode forward drop would otherwise dominate.
Input range and switching frequency flexibility
The minimum 1.8 V input means the regulator can continue delivering a regulated 3.3 V output even as the battery discharges below 2 V. Switching frequency is programmable from 300 kHz to 2 MHz via an external resistor. Lower frequencies improve efficiency by reducing switching losses; higher frequencies shrink the inductor footprint at the cost of increased FET switching losses and core loss in the magnetics. The positive output configuration and single-output channel suit point-of-load regulation for FPGAs, sensors, or RF power amplifiers requiring a clean, regulated rail above or below the input.
The 16-lead WFDFN package with an exposed thermal pad (supplier device package 16-DFN 5x4 mm) requires the pad to be soldered to a PCB copper plane for thermal dissipation. At 3 A output, the power loss (I² × Rds(on) + switching losses) can exceed 1.5 W; the board copper area and via array under the pad set the effective thermal resistance.