# ESD5621W-2

**WILLSEMI Will Semicon** · ESD And Surge Protection (TVS/ESD) · SOD-323F

ESD5621W-2 from WILLSEMI Will Semicon, in a SOD-323F. 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 | Pin1 | passive | One of the two terminals of this uni-directional TVS; the datasheet measures its clamping voltage and ESD ratings from pin 1 to pin 2, and the ESD5621W-2 (12 V class) has a reverse stand-off voltage VRWM of 12.0 V. |
| 2 | Pin2 | passive | The other terminal of this uni-directional TVS, serving as the reference for the pin 1 to pin 2 ratings, with reverse leakage IRM at most 0.1 µA at VRWM and junction capacitance of 300 pF typical and 400 pF maximum at 1 MHz, 0 V. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | WILLSEMI Will Semicon |
| Package | SOD-323F |
| Category | Circuit Protection |
| 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 |
|---|---|---|---|---|---|---|---|
| Reverse standoff voltage | VRWM |  |  | 12 | V |  | 3 |
| Breakdown voltage | VBR | 13 | 15 | 17 | V | IBR = 1mA | 3 |
| Reverse leakage current | IRM |  |  | 0.1 | μA | at VRWM | 3 |
| Forward voltage | VF | 0.45 |  | 1.25 | V | IF = 20mA | 3 |
| Junction capacitance |  |  | 300 | 400 | pF | F = 1MHz, VR =0V | 3 |
| Peak pulse power | Ppk |  |  | 1400 | W | tp=8/20μs | 2 |
| ESD according to IEC61000-4-2 air discharge | VESD | -30 |  | 30 | kV | IEC61000-4-2 air discharge | 2 |
| ESD according to IEC61000-4-2 contact discharge | VESD | -30 |  | 30 | kV | IEC61000-4-2 contact discharge | 2 |
| Junction temperature | TJ |  |  | 125 | oC |  | 2 |
| Operating temperature | TOP | -40 |  | 85 | oC |  | 2 |
| Lead temperature | TL |  |  | 260 | oC |  | 2 |
| Storage temperature | TSTG | -55 |  | 150 | oC |  | 2 |

## CAD (KiCad official)

- Symbol: `ESD5621W-2`
- Footprint: `Diode_SMD:D_SOD-323F`
- 3D model: SOD-323F (KiCad packages3D, STEP)
- 3D model files: `esd5621w-2-etched.step` / `esd5621w-2-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `esd5621w-2.step` / `esd5621w-2.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [WILLSEMI Will Semicon datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588902304901054464) (6 pp, sha256 `fcc9b68db464cac6`, retrieved 2026-10-15, 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/esd5621w-2-datasheet.pdf)