# CD74HCT85M

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

CD74HCT85M 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 | Most significant bit of word B; HCT input with VIL 0.8 V max and VIH 2 V min. |
| 2 | (A < B) IN | input | Cascading input for the A < B result from a lower-order comparator, used for serial or parallel expansion. |
| 3 | (A = B) IN | input | Cascading input for the A = B result from a lower-order comparator, used for serial or parallel expansion. |
| 4 | (A > B) IN | input | Cascading input for the A > B result from a lower-order comparator, used for serial or parallel expansion. |
| 5 | (A > B) OUT | output | Buffered output that goes high when word A is greater than word B, with fanout of 10 LSTTL loads. |
| 6 | (A = B) OUT | output | Buffered output that goes high when word A equals word B, with fanout of 10 LSTTL loads. |
| 7 | (A < B) OUT | output | Buffered output that goes high when word A is less than word B, with fanout of 10 LSTTL loads. |
| 8 | GND | power_in | Ground reference; continuous current through VCC or GND is limited to ±50 mA. |
| 9 | B0 | input | Least significant bit of word B. |
| 10 | A0 | input | Least significant bit of word A. |
| 11 | B1 | input | Bit 1 of word B. |
| 12 | A1 | input | Bit 1 of word A. |
| 13 | A2 | input | Bit 2 of word A. |
| 14 | B2 | input | Bit 2 of word B. |
| 15 | A3 | input | Most significant bit of word A. |
| 16 | VCC | power_in | Supply voltage, 4.5 V to 5.5 V for HCT types, with a 0.1 µF bypass capacitor recommended close to the pin. |

## Key specifications

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

## CAD (KiCad official)

- Symbol: `CD74HCT85M`
- Footprint: `Package_SO:SOIC-16_3.9x9.9mm_P1.27mm`
- 3D model: SOIC-16 (KiCad packages3D, STEP)
- 3D model files: `cd74hct85m-etched.step` / `cd74hct85m-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `cd74hct85m.step` / `cd74hct85m.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/cd74hct85.pdf) (27 pp, sha256 `1a8b9d560ba6e590`, retrieved 2026-11-05, 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/cd74hct85m-datasheet.pdf)