# ULN2074B

**STMicroelectronics** · Darlington Transistor Arrays · DIP-16

ULN2074B from STMicroelectronics, in a DIP-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 | C | passive | Collector (open output) of Darlington driver, rated 50 V minimum breakdown and up to 1.5 A. |
| 2 | E | passive | Emitter of Darlington driver, isolated from the other emitters on the ULN2074B. |
| 3 | B | input | Base (input) of Darlington driver, compatible with 5 V logic families, absolute maximum input voltage 30 V. |
| 4 | SUB | passive | Substrate pin, the reference for input voltage on the ULN2074B, to be connected to the most negative potential and used as heat-sink pin. |
| 5 | SUB | passive | Substrate pin, the reference for input voltage on the ULN2074B, to be connected to the most negative potential and used as heat-sink pin. |
| 6 | B | input | Base (input) of Darlington driver, compatible with 5 V logic families, absolute maximum input voltage 30 V. |
| 7 | E | passive | Emitter of Darlington driver, isolated from the other emitters on the ULN2074B. |
| 8 | C | passive | Collector (open output) of Darlington driver, rated 50 V minimum breakdown and up to 1.5 A. |
| 9 | C | passive | Collector (open output) of Darlington driver, rated 50 V minimum breakdown and up to 1.5 A. |
| 10 | E | passive | Emitter of Darlington driver, isolated from the other emitters on the ULN2074B. |
| 11 | B | input | Base (input) of Darlington driver, compatible with 5 V logic families, absolute maximum input voltage 30 V. |
| 12 | SUB | passive | Substrate pin, the reference for input voltage on the ULN2074B, to be connected to the most negative potential and used as heat-sink pin. |
| 13 | SUB | passive | Substrate pin, the reference for input voltage on the ULN2074B, to be connected to the most negative potential and used as heat-sink pin. |
| 14 | B | input | Base (input) of Darlington driver, compatible with 5 V logic families, absolute maximum input voltage 30 V. |
| 15 | E | passive | Emitter of Darlington driver, isolated from the other emitters on the ULN2074B. |
| 16 | C | passive | Collector (open output) of Darlington driver, rated 50 V minimum breakdown and up to 1.5 A. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | STMicroelectronics |
| Package | DIP-16 |
| Category | Transistors/Thyristors |
| Pins | 16 |

## CAD (KiCad official)

- Symbol: `ULN2074B`
- Footprint: `Package_DIP:DIP-16_W7.62mm`
- 3D model: DIP-16 (KiCad packages3D, STEP)
- 3D model files: `uln2074b-etched.step` / `uln2074b-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `uln2074b.step` / `uln2074b.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [STMicroelectronics datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8603079068946882560) (14 pp, sha256 `23625f675e9a4592`, retrieved 2026-10-11, tier: lcsc)
- **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/uln2074b-datasheet.pdf)