# SMDJ400A

**Littelfuse** · TVS · DO-214AB(SMCJ)

SMDJ400A from Littelfuse, in a DO-214AB(SMCJ). 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 | 1 | passive | Terminal 1 of an unpolarised fuse; either orientation. |
| 2 | 2 | passive | Terminal 2 of an unpolarised fuse; either orientation. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Littelfuse |
| Package | DO-214AB(SMCJ) |
| Category | TVS/Fuse/Board Level 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 |
|---|---|---|---|---|---|---|---|
| Breakdown Voltage | VBR | 447 |  | 494 | V | IT = 1 mA | 2 |
| Reverse Leakage Current | IR |  |  | 2 | µA | @ VR = 400 V | 2 |
| Maximum Clamping Voltage 10/1000µs | VC |  |  | 648 | V | @ Ipp 6.2 A (10/1000µs) | 2 |
| Maximum Peak Pulse Current 10/1000µs | Ipp |  |  | 6.2 | A | 10/1000µs | 2 |
| Maximum Clamping Voltage 8/20µs | VC |  |  | 837.21 | V | @ Ipp 23.5 A (8/20µs) | 2 |
| Maximum Peak Pulse Current 8/20µs | Ipp |  |  | 23.5 | A | 8/20µs | 2 |
| Maximum Temperature Coefficient of VBR | αT |  |  | 0.112 | %/C |  | 2 |
| Maximum Instantaneous Forward Voltage (Single Die) | VF |  |  | 3.5 | V | at 100 A, unidirectional only, single-die parts | 1 |
| Maximum Instantaneous Forward Voltage (Stacked Die) | VF |  |  | 5 | V | at 100 A, unidirectional only, stacked-die parts | 1 |
| Peak Pulse Power Dissipation (Single Die) | PPPM |  |  | 3000 | W | 10/1000µs test waveform (Fig.4), single die parts | 1 |
| Peak Pulse Power Dissipation (Stacked Die) | PPPM |  |  | 4000 | W | 10/1000µs test waveform (Fig.4), stacked-die parts | 1 |
| Power Dissipation on Infinite Heat Sink | PD |  |  | 6.5 | W | at TL = 50°C | 1 |
| Peak Forward Surge Current | IFSM |  |  | 300 | A | 8.3 ms single half sine wave | 1 |
| Operating Temperature Range | TJ | -65 |  | 150 | °C |  | 1 |
| Storage Temperature Range | TSTG | -65 |  | 175 | °C |  | 1 |
| Typical Thermal Resistance Junction to Lead | RθJL |  | 15 |  | °C/W |  | 1 |
| Typical Thermal Resistance Junction to Ambient | RθJA |  | 75 |  | °C/W |  | 1 |
| Reverse Stand-off Voltage | VR |  | 400 |  | V |  | 2 |

## Materials and finish

As the datasheet states them (page.json `metadata.appearance`; the 3D model's colours follow it).

| Part | Material | Colour / plating | Datasheet says | Page |
|---|---|---|---|---|
| contacts | copper |  | 2. Mounted on copper pad area of 0.31x0.31” (8.0 x 8.0mm) to each terminal. | 1 |

## CAD (KiCad official)

- Symbol: `SMDJ400A`
- Footprint: `Diode_SMD:D_SMC`
- 3D model: DO-214AB(SMCJ) (KiCad packages3D, STEP)

## Provenance

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

- **Datasheet:** [Littelfuse datasheet](docs/smdj400a-datasheet.pdf) (6 pp, sha256 `ce0f83e04ec5de82`, retrieved 2026-10-30, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins`, primary `two-terminal convention` (convention), consensus `off` (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/smdj400a-datasheet.pdf)