# UDZSTE-178.2B

**YONGYUTAI** · Zener Diodes · SOD-323

UDZSTE-178.2B from YONGYUTAI, in a SOD-323. 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 | K | passive | Cathode, the color-band end of the SOD-323 package (marked "-" in the outline drawing); Zener voltage 8.2V nominal (7.7V to 8.7V) at Izt=5mA. |
| 2 | A | passive | Anode, the end opposite the color band (marked "+" in the outline drawing); forward voltage 0.9V at IF=10mA. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | YONGYUTAI |
| Package | SOD-323 |
| 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 8.2 V) | Vz | 7.7 | 8.2 | 8.7 | V | Izt = 5 mA | 1 |
| Maximum Zener impedance | Zzt |  |  | 15 | Ω | @ Izt = 5 mA | 1 |
| Maximum Zener impedance (knee) | Zzk |  |  | 80 | Ω | @ Izk = 1.0 mA | 1 |
| Maximum reverse current | IR |  |  | 0.7 | uA | @ VR = 5.0 V | 1 |
| Temperature coefficient of Zener voltage |  | 3.2 |  | 6.2 | mV/℃ | @ IZTC = 5 mA | 1 |
| Power dissipation | Pd |  |  | 200 | mW |  | 1 |
| Storage temperature range | Ts | -65 |  | 150 | ℃ |  | 1 |
| Forward voltage | Vf |  | 0.9 |  | V | @IF=10mA | 1 |

## CAD (KiCad official)

- Symbol: `UDZSTE-178.2B`
- Footprint: `Diode_SMD:D_SOD-323`
- 3D model: SOD-323 (KiCad packages3D, STEP)
- 3D model files: `udzste-178-2b-etched.step` / `udzste-178-2b-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `udzste-178-2b.step` / `udzste-178-2b.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [YONGYUTAI datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590191735365001216) (5 pp, sha256 `c72a208771c1ed0c`, retrieved 2026-11-07, 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/udzste-178-2b-datasheet.pdf)