# MM1ZB18

**HUXN** · Zener Diodes · SOD-123

MM1ZB18 from HUXN, in a SOD-123. 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 | Cathode | passive | Cathode terminal of the MM1ZB18 Zener diode, which has a nominal Zener voltage of 18 V (17.64 to 18.36 V at 5 mA test current). |
| 2 | Anode | passive | Anode terminal of the MM1ZB18 Zener diode, used as the return side of the reverse-biased Zener clamp. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | HUXN |
| Package | SOD-123 |
| Category | Diodes |
| Pins | 2 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Zener voltage (nominal) | VZ | 17.64 | 18 | 18.36 | V | IZT = 5 mA; pulsed (20 ms) | 2 |
| Dynamic impedance | ZZT |  |  | 45 | Ω | IZT = 5 mA | 2 |
| Reverse leakage current | IR |  |  | 0.1 | µA | VR = 13 V | 2 |
| Forward voltage | VF |  |  | 0.9 | V | IF = 10 mA | 1 |
| Zener voltage tolerance |  | -2 |  | 2 | % |  | 1 |
| Power dissipation | Ptot |  |  | 500 | mW | Ta = 25 °C | 1 |
| Junction temperature | TJ |  |  | 150 | °C |  | 1 |
| Storage temperature range | TStg | -55 |  | 150 | °C |  | 1 |
| Thermal resistance junction to ambient air | RthA |  |  | 340 | °C/W |  | 1 |

## CAD (KiCad official)

- Symbol: `MM1ZB18`
- Footprint: `Diode_SMD:D_SOD-123F`
- 3D model: SOD-123 (KiCad packages3D, STEP)
- 3D model files: `mm1zb18-etched.step` / `mm1zb18-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mm1zb18.step` / `mm1zb18.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [HUXN datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8603182021032767488) (4 pp, sha256 `f4a0859d4da7bc74`, retrieved 2026-10-16, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-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/mm1zb18-datasheet.pdf)