Boost regulator for tight spaces
The TPS612592YFFT is a fixed 5.2 V step-up converter from Texas Instruments, built around a 3.9 A switch and a 3.5 MHz switching frequency. It accepts an input from 2.65 V up to 4.85 V, so it can run from a single Li-ion cell, a 3.3 V rail, or a 5 V USB bus. The output is positive and fixed at 5.2 V, with synchronous rectification built in to keep efficiency up at moderate loads.
Switch current and load budget
The 3.9 A switch current rating is the peak current the internal FET can handle cycle-by-cycle. For a boost from 3.3 V to 5.2 V, that translates to roughly 2 A continuous output current before the current-limit foldback kicks in — enough to power a small radio module or a sensor node with a bursty load. The 3.5 MHz switching frequency pushes the ripple into a range where a 1 µH inductor and 10 µF output cap keep the output ripple under 20 mV typical.
The 9-DSBGA package is a 0.5 mm pitch BGA — a 2-layer board can route it, but a 4-layer stack-up with a solid ground plane under the package improves thermal performance.