Fixed 5V boost with a 3.6 A switch
The TPS61032RSAR is a fixed 5 V output boost converter from TI, built around a 3.6 A internal switch.
Input range and output: the battery-powered fit
The 1.8 V minimum input lets this part run from a nearly depleted Li-Ion cell or a pair of alkalines in series. At the top end, 5.5 V max input means it tolerates a 5 V rail with margin but won't survive a 12 V bus — it's a low-voltage boost, not a wide-VIN part. The fixed 5 V output is non-negotiable: if your load needs 3.3 V or 12 V, this isn't the regulator. For a 5 V rail from a battery or a 3.3 V intermediate bus, it's a direct fit.
Package and thermal: the exposed pad matters
Without it, the junction temperature climbs fast under the 3.6 A switch current. Layout engineers should budget for at least four vias in the pad and a solid copper pour on the bottom layer.