AM26C31IDR from Texas Instruments, in a SOIC-16. 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	1A	input	Driver 1 single-ended input. TTL/CMOS-compatible logic input (VIH ≥ 2 V, VIL ≤ 0.8 V) that drives the differential 1Y/1Z output pair.
2	1Y	tri_state	Driver 1 non-inverting differential output. 3-state output capable of ±20 mA drive into a 100 Ω line; forced to high-impedance when the driver is disabled via the enable pins.
3	1Z	tri_state	Driver 1 inverted differential output. 3-state complementary output paired with 1Y; goes high-impedance when disabled.
4	G	input	Active-high output enable, common to all four drivers. When G=H and G-bar=L, all Y/Z outputs are active; otherwise outputs are placed in the high-impedance state.
5	2Z	tri_state	Driver 2 inverted differential output. 3-state complementary output paired with 2Y.
6	2Y	tri_state	Driver 2 non-inverting differential output. 3-state output paired with 2Z; capable of ±20 mA into a 100 Ω line.
7	2A	input	Driver 2 single-ended TTL/CMOS input driving the differential 2Y/2Z output pair.
8	GND	power_in	Device ground reference (0 V). All voltages are referenced to this network ground terminal.
9	3A	input	Driver 3 single-ended TTL/CMOS input driving the differential 3Y/3Z output pair.
10	3Y	tri_state	Driver 3 non-inverting differential output. 3-state output paired with 3Z.
11	3Z	tri_state	Driver 3 inverted differential output. 3-state complementary output paired with 3Y.
12	G	input	Active-low output enable (G-bar), common to all four drivers. Must be LOW (and G HIGH) for outputs to be active; otherwise outputs go to high-impedance.
13	4Z	tri_state	Driver 4 inverted differential output. 3-state complementary output paired with 4Y.
14	4Y	tri_state	Driver 4 non-inverting differential output. 3-state output paired with 4Z.
15	4A	input	Driver 4 single-ended TTL/CMOS input driving the differential 4Y/4Z output pair.
16	VCC	power_in	Positive supply voltage, 4.5 V to 5.5 V (5 V nominal). ICC ≈ 100 µA typical; bypass to GND with a 0.1 µF capacitor close to the pin.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	SOIC-16
Category	Logic
Pins	16

Ordering variants

Same part, different packaging or reel option.

AM26C31IDRD
AM26C31IDR
AM26C31IDRIDG4
AM26C31IDRDB
AM26C31IDRPW
AM26C31IDRNS
AM26C31IDRN
AM26C31IDRJ
AM26C31IDRW
AM26C31IDRFK

CAD (KiCad official)

Symbol: AM26C31IDR
Footprint: Package_SO:SOIC-16_3.9x9.9mm_P1.27mm
3D model: SOIC-16 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`am26c31idr.step`	217 KB	You want the bare part, or you mark your own boards.
`am26c31idr-etched.step`	2.5 MB	You want the part with `AM26C31IDR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 623 faces against 267 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 (39 pp, sha256 c5ab343a1319884d, 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