What this boost LED driver does on your board
The TPS61040DRVR is a DC DC Regulator built for driving LEDs in backlight applications — it steps up a low input voltage to a regulated 28 V output, switching at 1 MHz to keep the inductor small. The internal switch handles 350 mA peak, which means you can drive a string of series-connected white LEDs without adding an external transistor. PWM dimming is supported directly on the enable pin, so the microcontroller can control brightness without an extra DAC or PWM generator.
Supply rails and temperature range
Input voltage spans 1.8 V to 6 V, covering single-cell Li-Ion, two alkaline cells, or a 3.3 V / 5 V rail — the minimum 1.8 V lets it run from a nearly depleted battery.
Surface-mount only; no through-hole variant exists. The small footprint makes it a fit for compact portable or display assemblies.