# SMAJ78A

**DOWO** · TVS · SMA(DO-214AC)

SMAJ78A from DOWO, in a SMA(DO-214AC). 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 (cathode) | passive | The color band marks the cathode end on this unidirectional SMAJ78A, rated for a working peak reverse voltage VRWM of 78.0 V with a maximum reverse leakage IR of 1 uA at VRWM. |
| 2 | A (anode) | passive | The end opposite the color band is the anode; the device is rated for 400 W peak pulse power (10/1000 us waveform) and clamps to a maximum of 126.0 V at a peak pulse current IPP of 3.17 A. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | DOWO |
| Package | SMA(DO-214AC) |
| Category | Circuit Protection |
| Pins | 2 |

## CAD (KiCad official)

- Symbol: `SMAJ78A`
- Footprint: `Diode_SMD:D_SMA`
- 3D model: SMA(DO-214AC) (KiCad packages3D, STEP)
- 3D model files: `smaj78a-etched.step` / `smaj78a-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `smaj78a.step` / `smaj78a.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [DOWO datasheet](docs/smaj78a-datasheet.pdf) (4 pp, sha256 `4198cd8e3dc5e7ef`, retrieved 2026-10-21, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (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/smaj78a-datasheet.pdf)