UM3352EESA from Union Semiconductor, in a SOP-8. 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	RO	output	Receiver Output. If (A-B) ≥ -50mV, RO is high; if (A-B) ≤ -200mV, RO is low. High-impedance when RE is high.
2	RE	input	Receiver Output Enable (active low). Drive RE low to enable the receiver; RO is high-impedance when RE is high. Drive RE high and DE low to enter low-power shutdown mode.
3	DE	input	Driver Enable. Drive DE high to enable the drivers; driver outputs A/B are high-impedance when DE is low. Drive RE high and DE low to enter low-power shutdown mode.
4	DI	input	Driver Input. A low on DI forces output A low and output B high; a high on DI forces output A high and output B low.
5	GND	power_in	Ground reference.
6	A	bidirectional	Non-Inverting Receiver Input and Non-Inverting Driver Output (RS-485 bus line A). Rated -7V to +12V common-mode; ±15kV HBM ESD protection.
7	B	bidirectional	Inverting Receiver Input and Inverting Driver Output (RS-485 bus line B). Rated -7V to +12V common-mode; ±15kV HBM ESD protection.
8	VCC	power_in	Power supply for the RS-485 transceiver. Operating range +5V ±5%; absolute maximum +7V.

Key specifications

Parameter	Value
Manufacturer	Union Semiconductor
Package	SOP-8
Category	Comm/UART
Pins	8

Ordering variants

Same part, different packaging or reel option.

UM3352EESA
UM3352EESAEEPA

CAD (KiCad official)

Symbol: UM3352EESA
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SOP-8 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`um3352eesa.step`	122 KB	You want the bare part, or you mark your own boards.
`um3352eesa-etched.step`	2.3 MB	You want the part with `UM3352EESA` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 560 faces against 147 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: Union Semiconductor datasheet (14 pp, sha256 ed13caca939f352d, 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