Fixed 5 V boost in a 9-bump DSBGA
The Texas Instruments TPS61256YFFR is a step-up (boost) converter that delivers a fixed 5 V output from an input range of 2.5 V to 4.85 V. The integrated switch is rated for 2.4 A, which sets the maximum deliverable output current at 5 V — typically around 1 A depending on the input voltage and efficiency.
What the 2.4 A switch rating means for your BOM
The 2.4 A switch current is the peak current the internal FET can handle cycle-by-cycle. For a boost converter, the input current is higher than the output current, so a 2.4 A switch limits the output to roughly 1 A at 5 V from a 3.3 V input, assuming 85% efficiency. If your load pulls 1.2 A at 5 V, this part will current-limit or drop out — size up to the TPS61258 or add a second stage. The fixed 5 V output means no external feedback divider, saving two resistors and one feedback node on the layout.
Package and layout: 9-DSBGA
Not a hand-solder part — you need a pick-and-place and a reflow oven.
It works in outdoor IoT gateways, portable instruments, battery-powered sensors, and any device that sees a parking lot in winter or a hot enclosure in summer. Not qualified to AEC-Q100, so skip it for under-hood or chassis-mounted automotive designs unless you plan your own qualification.
