# SM5908

**STMicroelectronics** · TVS · SMC

SM5908 from STMicroelectronics, in a SMC. 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 of the unidirectional Transil, marked by the cathode bar on the package; connects to the protected line (positive side), with 5 V stand-off voltage (VRM) and 6 V min breakdown voltage at 1 mA. |
| 2 | A | passive | Anode of the unidirectional Transil, typically connected to ground/reference; device handles 1500 W peak pulse power (10/1000 µs). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | STMicroelectronics |
| Package | SMC |
| 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 |
|---|---|---|---|---|---|---|---|
| Leakage current | IRM |  |  | 300 | µA | @ VRM = 5 V | 3 |
| Stand-off voltage | VRM |  | 5 |  | V |  | 3 |
| Breakdown voltage | VBR | 6 |  |  | V | @ IR = 1 mA, pulse test tp < 50 ms | 3 |
| Clamping voltage | VCL |  |  | 7.6 | V | @ IPP = 30 A, 10/1000 µs | 3 |
| Clamping voltage | VCL |  |  | 8 | V | @ IPP = 60 A, 10/1000 µs | 3 |
| Clamping voltage | VCL |  |  | 8.5 | V | @ IPP = 120 A, 10/1000 µs | 3 |
| Peak pulse power dissipation | PPP |  |  | 1500 | W | Tj initial = Tamb, Tamb = 25 °C | 2 |
| Storage temperature range | Tstg | -65 |  | 175 | °C |  | 2 |
| Operating junction temperature range | Tj | -55 |  | 175 | °C |  | 2 |
| Maximum lead temperature for soldering | TL |  |  | 260 | °C | during 10 s | 2 |
| Thermal resistance junction to leads | Rth(j-l) |  | 15 |  | °C/W | SMC | 2 |
| Thermal resistance junction to ambient | Rth(j-a) |  | 90 |  | °C/W | on printed circuit on recommended pad layout, SMC | 2 |
| Voltage temperature coefficient | αT |  | 5.7 |  | 10-4/°C |  | 3 |
| Capacitance | C |  | 9500 |  | pF |  | 3 |

## CAD (KiCad official)

- Symbol: `SM5908`
- Footprint: `Diode_SMD:D_SMC`
- 3D model: SMC (KiCad packages3D, STEP)
- 3D model files: `sm5908-etched.step` / `sm5908-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `sm5908.step` / `sm5908.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [STMicroelectronics datasheet](https://www.st.com/resource/en/datasheet/sm5908.pdf) (9 pp, sha256 `cd9d5412f7db212a`, retrieved 2026-10-31, tier: manufacturer)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-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/sm5908-datasheet.pdf)