LSF0108PWR from Texas Instruments, in a TSSOP-20. 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	GND	power_in	Ground reference for the device.
2	Vref_A	power_in	Reference supply voltage for the low-voltage (A) side. Operational range 0.65 V to (Vref_B - 0.6 V), max 5.5 V. Sets the A-side pass-FET bias level.
3	A1	bidirectional	Auto-bidirectional data port channel 1, A-side (low-voltage side). Connects through internal pass-FET switch to B1. Operating I/O range 0 to 5.5 V.
4	A2	bidirectional	Auto-bidirectional data port channel 2, A-side. Connects through internal pass-FET switch to B2.
5	A3	bidirectional	Auto-bidirectional data port channel 3, A-side. Connects through internal pass-FET switch to B3.
6	A4	bidirectional	Auto-bidirectional data port channel 4, A-side. Connects through internal pass-FET switch to B4.
7	A5	bidirectional	Auto-bidirectional data port channel 5, A-side. Connects through internal pass-FET switch to B5.
8	A6	bidirectional	Auto-bidirectional data port channel 6, A-side. Connects through internal pass-FET switch to B6.
9	A7	bidirectional	Auto-bidirectional data port channel 7, A-side. Connects through internal pass-FET switch to B7.
10	A8	bidirectional	Auto-bidirectional data port channel 8, A-side. Connects through internal pass-FET switch to B8.
11	B8	bidirectional	Auto-bidirectional data port channel 8, B-side (high-voltage side). Connects through internal pass-FET switch to A8.
12	B7	bidirectional	Auto-bidirectional data port channel 7, B-side. Connects through internal pass-FET switch to A7.
13	B6	bidirectional	Auto-bidirectional data port channel 6, B-side. Connects through internal pass-FET switch to A6.
14	B5	bidirectional	Auto-bidirectional data port channel 5, B-side. Connects through internal pass-FET switch to A5.
15	B4	bidirectional	Auto-bidirectional data port channel 4, B-side. Connects through internal pass-FET switch to A4.
16	B3	bidirectional	Auto-bidirectional data port channel 3, B-side. Connects through internal pass-FET switch to A3.
17	B2	bidirectional	Auto-bidirectional data port channel 2, B-side. Connects through internal pass-FET switch to A2.
18	B1	bidirectional	Auto-bidirectional data port channel 1, B-side. Connects through internal pass-FET switch to A1.
19	Vref_B	power_in	Reference supply voltage for the high-voltage (B) side. Must be between Vref_A + 0.6 V and 5.5 V. Sets the B-side pass-FET bias level.
20	EN	input	Enable input; when high enables the pass-FET switches, when low forces I/O pins to high impedance. Connect to Vref_B through a ~200 kΩ bias resistor. Switch-mode enable voltage is 1.5 V to 5.5 V.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	TSSOP-20
Category	Logic
Pins	20

Ordering variants

Same part, different packaging or reel option.

LSF0108PWR
LSF0108PWRDGS
LSF0108PWRDGSR
LSF0108PWRRKS
LSF0108PWRRKSR

CAD (KiCad official)

Symbol: LSF0108PWR
Footprint: Package_SO:TSSOP-20_4.4x6.5mm_P0.65mm
3D model: TSSOP-20 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`lsf0108pwr.step`	267 KB	You want the bare part, or you mark your own boards.
`lsf0108pwr-etched.step`	2.8 MB	You want the part with `LSF0108PWR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 703 faces against 327 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: Texas Instruments datasheet (36 pp, sha256 9ebaeb18807278a1, 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