Small boost converter that steps a 1.8 to 6 V input up to as much as 28 V, using a fixed 400 mA internal switch and a resistor divider at FB to set the output. The high output ceiling suits it to biasing LCDs, small LED strings, and other rails that need more voltage than the battery provides, and an EN pin shuts it to a low quiescent state. It fits a SOT-23-5 with just an inductor, diode, and two capacitors. A compact general-purpose step-up.

Pinout

Pin	Name	Type	Function
1	SW	output	Switch pin, connected to the drain of the internal power MOSFET. Connect the inductor and Schottky diode to this pin. Maximum switch voltage 30V.
2	GND	power_in	Device ground reference.
3	FB	input	Feedback pin. Connect to the external resistor divider from VOUT to program the output voltage. Internal reference 1.233V (trip point 1.208V to 1.258V).
4	EN	input	Enable pin. Pulling this pin to ground forces the device into shutdown mode reducing supply current below 1uA. Must not be left floating. VIH >= 1.3V, VIL <= 0.4V.
5	VIN	power_in	Supply voltage input, 1.8V to 6V operating range (7V absolute max).

Key specifications

Parameter	Value
Type	Boost (step-up) converter
Input	1.8-6 V
Output	Up to 28 V (adjustable)
Switch current	400 mA
Switching freq	Up to 1 MHz
Enable	EN pin
Package	SOT-23-5

Ordering variants

Same part, different packaging or reel option.

TPS61041DBVR (SOT-23-5)
TPS61040DBVR (250 mA switch)

CAD (KiCad official)

Symbol: Regulator_Switching:TPS61041DBV (KiCad official)
Footprint: Package_TO_SOT_SMD:SOT-23-5
3D model: SOT-23-5 (KiCad packages3D, STEP)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

Datasheet: Texas Instruments datasheet (39 pp, sha256 6cdca27bfce2aa90, retrieved 2026-08-17, tier: manufacturer)
Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF