SIT3485ESA from SIT, 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. When /RE is low: if A-B >= +200 mV, RO outputs high; if A-B <= -200 mV, RO outputs low. High-Z when receiver is disabled (/RE = high). VOH >= VCC-1.5 V at IOUT = -2.5 mA; VOL <= 0.4 V at IOUT = +2.5 mA.
2	/RE	input	Receiver output enable, active-low. Low = receiver output enabled (RO active). High = receiver disabled (RO high-impedance). /RE high AND DE low places the device into low-power shutdown mode. VIH >= 2.0 V, VIL <= 0.8 V.
3	DE	input	Driver output enable, active-high. High = driver A/B outputs enabled. Low = driver outputs high-impedance. DE low AND /RE high enters low-power shutdown. VIH >= 2.0 V, VIL <= 0.8 V.
4	DI	input	Driver data input. When driver is enabled: DI low drives A low and B high; DI high drives A high and B low. VIH >= 2.0 V, VIL <= 0.8 V, input current +/-2 uA.
5	GND	power_in	Ground reference (0 V). All voltages referenced to this pin.
6	A	bidirectional	RS-485 non-inverting bus I/O. Receiver non-inverting input and driver non-inverting output. Common-mode range -7 V to +12 V; receiver input resistance >= 96 kOhm (1/8 unit load). Includes integrated transient protection.
7	B	bidirectional	RS-485 inverting bus I/O. Receiver inverting input and driver inverting output. Common-mode range -7 V to +12 V; receiver input resistance >= 96 kOhm (1/8 unit load). Includes integrated transient protection.
8	VCC	power_in	Supply voltage input. Operating range 3.0 V to 3.6 V (nominal 3.3 V). Absolute max +7 V. Typical supply current 520-540 uA active; 0.5 uA in shutdown. Decouple with a 0.1 uF ceramic capacitor to GND.

Key specifications

Parameter	Value
Manufacturer	SIT
Package	SOP-8
Category	Interface
Pins	8

Ordering variants

Same part, different packaging or reel option.

SIT3485ESA

CAD (KiCad official)

Symbol: SIT3485ESA
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
`sit3485esa.step`	122 KB	You want the bare part, or you mark your own boards.
`sit3485esa-etched.step`	2.3 MB	You want the part with `SIT3485ESA` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 557 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: SIT datasheet (13 pp, sha256 f9261a7d13245d2a, 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