TMI3253S from TMI, in a SOT-23-6. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin	Name	Type	Function
1	BS	passive	Bootstrap. A capacitor connected between LX and BS pins is required to form a floating supply across the high-side switch driver. Absolute-maximum BS voltage is 26V; BS-to-LX max is 6V.
2	GND	power_in	Ground return pin for the IC and the low-side power MOSFET source.
3	FB	input	Output-voltage feedback input. Connect to the center tap of the external resistor divider. Regulated to VREF=0.6V typ (TMI3253S). Absolute maximum -0.3V to 6V.
4	EN	input	Enable input. Drive logic-high to enable the IC; drive logic-low to disable and enter micro-power shutdown. Do not float. EN rising threshold ~0.95V (0.85V-1.05V), 180mV hysteresis. Abs-max 20V.
5	IN	power_in	Power supply input. Operating range 4.5V to 18V; UVLO rising ~4.3V. Absolute maximum 20V. Bypass with a low-ESR ceramic capacitor (22µF typical) to GND.
6	LX	power_out	Switching node. Common drain of the integrated high-side and low-side power MOSFETs; connects to the external inductor. Abs-max -0.3V to 20V (-4.5V to 22V transient <10ns).

Key specifications

Parameter	Value
Manufacturer	TMI
Package	SOT-23-6
Category	PMIC
Pins	6

Ordering variants

Same part, different packaging or reel option.

TMI3253S
TMI3253T

CAD (KiCad official)

Symbol: TMI3253S
Footprint: Package_TO_SOT_SMD:SOT-23-6
3D model: SOT-23-6 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`tmi3253s.step`	97 KB	You want the bare part, or you mark your own boards.
`tmi3253s-etched.step`	1.8 MB	You want the part with `TMI3253S` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 445 faces against 117 in the bare model. It survives export, section views, and rendering in any CAD tool, and it drops straight into KiCad or Fusion with no extra setup.

Provenance

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

Datasheet: TMI datasheet (16 pp, sha256 b58c2a4a18985f81, retrieved 2026-08-17, tier: lcsc)
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