# BSMD1812-250-8V

**BHFUSE** · Resettable Fuses · 1812

BSMD1812-250-8V from BHFUSE, in a 1812. 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 | BHFUSE |
| Package | 1812 |
| 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 |
|---|---|---|---|---|---|---|---|
| Trip current (minimum current at which device trips, 25°C still air) | Itrip | 5 |  |  | A | 25°C still air | 2 |
| Minimum resistance (initial, un-soldered state) | Rmin | 0.015 |  |  | Ω | initial un-soldered state | 2 |
| Hold current (maximum current passed without tripping) | Ihold |  |  | 2.5 | A | 25°C still air | 2 |
| Maximum resistance R1max | R1max |  |  | 0.09 | Ω | 25°C, measured one hour after tripping or reflow soldering at 260°C for 20 sec | 2 |
| Maximum voltage (rated voltage, withstand without damage) | Vmax |  |  | 8 | Vdc | at rated current (Imax) | 2 |
| Maximum fault current (withstand without damage) | Imax |  |  | 40 | A | at rated voltage (Vmax) | 2 |
| Ambient operating temperature |  | -40 |  | 85 | °C | ambient operating conditions, series-wide statement | 5 |
| Resistance change, passive aging |  | -5 |  | 5 | % | +85°C, 1000 hours (typical) | 5 |
| Resistance change, humidity aging |  | -5 |  | 5 | % | +85°C, 85% R.H., 168 hours (typical) | 5 |
| Resistance change, thermal shock |  | -33 |  | 33 | % | +85°C to -40°C, 20 times (typical) | 5 |
| Maximum surface temperature in tripped state |  |  |  | 125 | °C | device in tripped state | 5 |
| Power dissipated in tripped state (typical) | Pd |  | 1 |  | W | tripped state, 25°C still air | 2 |
| Time to trip | Time to trip |  | 2.5 |  | Sec | at 8.00 A | 2 |

## CAD (KiCad official)

- Symbol: `BSMD1812-250-8V`
- Footprint: `Fuse:Fuse_1812_4532Metric`
- 3D model: 1812, generated from the KiCad footprint (body from the F.Fab outline, terminals on the pads, 0.9 mm nominal _1806_ height). Neither the vendor nor KiCad ships a 3D model for this package, so the dimensions are nominal, not the manufacturer's CAD (STEP)
- 3D model files: `bsmd1812-250-8v-etched.step` / `bsmd1812-250-8v-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bsmd1812-250-8v.step` / `bsmd1812-250-8v.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [BHFUSE datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588918033746575360) (10 pp, sha256 `a7f7e8936d26d547`, retrieved 2026-10-18, 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/bsmd1812-250-8v-datasheet.pdf)