SN65HVD78DR from Texas Instruments, in a SOIC-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	R	output	Receive data output. CMOS-level output driven from the differential receiver comparing bus pins A and B. Output current range +/-8 mA.
2	RE	input	Active-low receiver enable. When low, the receiver output R is enabled; when high, R is high-impedance. Tie low with DE low for standby.
3	DE	input	Active-high driver enable. When high, the differential driver on A/B is enabled; when low, driver outputs are high-impedance.
4	D	input	Driver data input. CMOS-level logic input driving the differential bus outputs A and B when DE is asserted. 5-V tolerant.
5	GND	power_in	Local device ground / reference potential.
6	A	bidirectional	Non-inverting RS-485 differential bus I/O. Driver output or receiver input, complementary to B. Wide common-mode range (-7 V to 12 V) and robust bus ESD.
7	B	bidirectional	Inverting RS-485 differential bus I/O. Driver output or receiver input, complementary to A. Wide common-mode range (-7 V to 12 V) and robust bus ESD.
8	VCC	power_in	Supply voltage, 3.0 V to 3.6 V (3.3 V nominal). Bypass to GND with a local 100 nF ceramic capacitor.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	SOIC-8
Category	Interface
Pins	8

Ordering variants

Same part, different packaging or reel option.

SN65HVD78DR
SN65HVD78DRD
SN65HVD78DRDGK
SN65HVD78DRDGKR
SN65HVD78DRB
SN65HVD78DRBR

CAD (KiCad official)

Symbol: SN65HVD78DR
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SOIC-8 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`sn65hvd78dr.step`	122 KB	You want the bare part, or you mark your own boards.
`sn65hvd78dr-etched.step`	2.3 MB	You want the part with `SN65HVD78DR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 558 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: Texas Instruments datasheet (47 pp, sha256 b46f5803fa8302f9, 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