TX6143 from XDS, in a SOT-89-5. 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	SW	output	Switch node - drain of the internal 60V power MOSFET (RDSon ~300 mΩ, max 1.2A). Connects to the inductor / freewheel Schottky cathode in the buck topology.
2	VSS	power_in	Chip ground / return for internal MOSFET source and control circuitry.
3	DIM	input	Brightness/dimming control input. Accepts PWM (up to 20 kHz) or analog (0.5V-2.5V) dimming; VIH ≥ 2.5V, VIL ≤ 0.3V. Internal ~500 kΩ pull-up to a 5V internal LDO - leave floating if dimming is not used. VDIM absolute-max is 6V. Output shuts off (standby) when DIM < 0.3V.
4	CS	input	High-side current-sense input. External sense resistor RCS between VIN and CS sets the LED current: ILED ≈ 0.2V / RCS. Hysteretic thresholds are 240 mV (peak) and 160 mV (valley) across VIN-CS. Input bias ~10 µA.
5	VIN	power_in	Main supply input, 5.5V to 60V operating (68V absolute max). UVLO rising ≈ 5.1V with 0.4V hysteresis. Bypass with 47-100 µF bulk capacitor rated above max VIN. Standby current ~320 µA at 12V when DIM=0.

Key specifications

Parameter	Value
Manufacturer	XDS
Package	SOT-89-5
Category	LED-drv
Pins	5

CAD (KiCad official)

Symbol: TX6143
Footprint: Package_TO_SOT_SMD:SOT-89-5
3D model: SOT-89-5 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`tx6143.step`	86 KB	You want the bare part, or you mark your own boards.
`tx6143-etched.step`	970 KB	You want the part with `TX6143` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 244 faces against 26 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: XDS datasheet (10 pp, sha256 3379b085ea49eafe, retrieved 2026-08-17, tier: lcsc)
Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
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