# SN74LS85DR

**Texas Instruments** · Digital Comparators · SOIC-16

SN74LS85DR from Texas Instruments, in a SOIC-16. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | B3 | input | Word B comparing input, bit 3 (most significant bit). |
| 2 | A<Bin | input | Cascading input A<B from the less-significant stage. |
| 3 | A=Bin | input | Cascading input A=B from the less-significant stage; must be held high on the stage handling the least-significant bits. |
| 4 | A>Bin | input | Cascading input A>B from the less-significant stage. |
| 5 | A>Bout | output | Output that goes high when word A is greater than word B. |
| 6 | A=Bout | output | Output that goes high when word A equals word B. |
| 7 | A<Bout | output | Output that goes high when word A is less than word B. |
| 8 | GND | power_in | Ground. |
| 9 | B0 | input | Word B comparing input, bit 0 (least significant bit). |
| 10 | A0 | input | Word A comparing input, bit 0 (least significant bit). |
| 11 | B1 | input | Word B comparing input, bit 1. |
| 12 | A1 | input | Word A comparing input, bit 1. |
| 13 | A2 | input | Word A comparing input, bit 2. |
| 14 | B2 | input | Word B comparing input, bit 2. |
| 15 | A3 | input | Word A comparing input, bit 3 (most significant bit). |
| 16 | VCC | power_in | Supply voltage. |

## Key specifications

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

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Operating free-air temperature range (ordering table, SN74LS85DR) |  | 0 |  | 70 | °C | Op temp column of Package Option Addendum for SN74LS85DR (SOIC D 16) | 9 |

## CAD (KiCad official)

- Symbol: `SN74LS85DR`
- Footprint: `Package_SO:SOIC-16_3.9x9.9mm_P1.27mm`
- 3D model: SOIC-16 (KiCad packages3D, STEP)
- 3D model files: `sn74ls85dr-etched.step` / `sn74ls85dr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `sn74ls85dr.step` / `sn74ls85dr.glb` are the bare package body.

## Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

- **Datasheet:** [Texas Instruments datasheet](https://www.ti.com/lit/ds/symlink/sn74ls85.pdf) (23 pp, sha256 `0af6f0e90f511213`, retrieved 2026-10-18, tier: manufacturer)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (text+vision), consensus `claude-opus-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/sn74ls85dr-datasheet.pdf)