THVD1400DR 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. Digital CMOS output driven by the differential receiver comparing bus pins A and B. VOH ≥ VCC-0.4 V at IOH = -4 mA; VOL ≤ 0.4 V at IOL = 4 mA.
2	RE	input	Receiver enable, active low. Digital input with internal 2-MΩ pull-up to VCC. When low, the receiver is enabled and drives pin R; when high, R goes to high-impedance.
3	DE	input	Driver enable, active high. Digital input with internal 2-MΩ pull-down to GND. When high, the driver is enabled and drives bus pins A and B; when low, A/B go to high-impedance.
4	D	input	Driver data input. Digital CMOS input; logic level driven onto the differential bus (A/B) when DE is high. VIH ≥ 2 V, VIL ≤ 0.8 V.
5	GND	power_in	Device ground reference.
6	A	bidirectional	Non-inverting RS-485 differential bus I/O port (complementary to B). Bus voltage range -7 V to +12 V; ±12-kV IEC 61000-4-2 contact ESD protection; ±16-V absolute-max fault voltage; 1/8 unit load.
7	B	bidirectional	Inverting RS-485 differential bus I/O port (complementary to A). Bus voltage range -7 V to +12 V; ±12-kV IEC 61000-4-2 contact ESD protection; ±16-V absolute-max fault voltage; 1/8 unit load.
8	VCC	power_in	Supply voltage input, 3 V to 5.5 V (nominal 3.3 V or 5 V). Quiescent supply current 1.5 mA typical; standby current < 1 µA.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	SOIC-8
Category	Comm/UART
Pins	8

Ordering variants

Same part, different packaging or reel option.

THVD1400DRD
THVD1400DR
THVD1400DRL
THVD1400DRLR

CAD (KiCad official)

Symbol: THVD1400DR
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
`thvd1400dr.step`	122 KB	You want the bare part, or you mark your own boards.
`thvd1400dr-etched.step`	1.8 MB	You want the part with `THVD1400DR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 475 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 (33 pp, sha256 5ba9785d9fb8dc87, 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