SN75451BDR 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	1A	input	Channel 1 logic input A. TTL-compatible, diode-clamped input to the channel-1 AND gate. VIH ≥ 2 V, VIL ≤ 0.8 V; IIH ≤ 40 µA, IIL ≤ -1.6 mA at VCC = 5 V.
2	1B	input	Channel 1 logic input B. TTL-compatible, diode-clamped input to the channel-1 AND gate. Same DC levels as 1A (VIH ≥ 2 V, VIL ≤ 0.8 V).
3	1Y	output	Channel 1 driver output. Open-collector npn transistor, off-state voltage up to 30 V, sinks 300 mA continuous (500 mA peak, tw ≤ 10 ms, DC ≤ 50%). VOL ≤ 0.4 V at IOL = 100 mA. Requires an external pull-up/load to the switched supply.
4	GND	power_in	Device ground / emitter return for both output transistors. Connect to system 0 V with low-inductance path to handle the switched output currents.
5	2Y	output	Channel 2 driver output. Open-collector npn transistor, off-state voltage up to 30 V, sinks 300 mA continuous (500 mA peak). VOL ≤ 0.4 V at IOL = 100 mA. Requires an external pull-up/load.
6	2A	input	Channel 2 logic input A. TTL-compatible, diode-clamped input to the channel-2 AND gate. VIH ≥ 2 V, VIL ≤ 0.8 V.
7	2B	input	Channel 2 logic input B. TTL-compatible, diode-clamped input to the channel-2 AND gate. VIH ≥ 2 V, VIL ≤ 0.8 V.
8	VCC	power_in	Positive logic-supply input. Recommended 4.75 V to 5.25 V (SN7545xB commercial grade), absolute max 7 V. Supplies only the TTL front end; the open-collector outputs are switched from an external load supply up to 30 V.

Key specifications

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

Ordering variants

Same part, different packaging or reel option.

SN75451BDRD
SN75451BDR
SN75451BDRP
SN75451BDRPS
SN75451BDRJG
SN75451BDRFK

CAD (KiCad official)

Symbol: SN75451BDR
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
`sn75451bdr.step`	122 KB	You want the bare part, or you mark your own boards.
`sn75451bdr-etched.step`	2.1 MB	You want the part with `SN75451BDR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 518 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 (34 pp, sha256 52e09dcf54bec812, 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