# FSMD050-R

**Fuzetec Tech** · Resettable Fuses · 1812

FSMD050-R from Fuzetec Tech, 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 | One terminal pad of the non-polarized PTC resettable fuse (pure tin), rated IH 0.50 A hold, IT 1.00 A trip, 16.0 VDC max, 100 A max fault current. |
| 2 | 2 | passive | Second terminal pad of the non-polarized PTC resettable fuse (pure tin), interchangeable with the other pad; recommended pad layout is given for all 1812 series. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Fuzetec Tech |
| 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 |
|---|---|---|---|---|---|---|---|
| Hold current | IH |  |  | 0.5 | A | 23℃ still air | 1 |
| Trip current | IT | 1 |  |  | A | 23℃ still air | 1 |
| Rated voltage (maximum voltage device can withstand at rated current) | VMAX |  |  | 16 | VDC | At rated current IMAX | 1 |
| Maximum fault current (at rated voltage) | IMAX |  |  | 100 | A | At rated voltage VMAX | 1 |
| Maximum time to trip |  |  |  | 0.15 | Sec | Test current 8.0 A | 1 |
| Minimum device resistance prior to tripping (RMIN) | RMIN | 0.15 |  |  | Ohm | 23℃ prior to tripping | 1 |
| Maximum device resistance after tripping (R1MAX) | R1MAX |  |  | 1 | Ohm | 23℃, measured 1 hour after tripping or reflow soldering of 260℃ for 20 seconds | 1 |
| Operating temperature range |  | -40 |  | 85 | ℃ | Temperature Range, from Summary | 1 |
| Typical power dissipated in tripped state | Pd |  | 0.8 |  | W | Tripped state, 23℃ still air | 1 |

## 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 |  | tin | Terminal pad material: Pure Tin Soldering characteristics: Meets EIA specification RS 186-9E, ANSI/J-std-002 Category 3 | 4 |

## CAD (KiCad official)

- Symbol: `FSMD050-R`
- 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: `fsmd050-r-etched.step` / `fsmd050-r-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `fsmd050-r.step` / `fsmd050-r.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Fuzetec Tech datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8600588119230472192) (5 pp, sha256 `7524936834e45601`, retrieved 2026-10-19, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (text+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/fsmd050-r-datasheet.pdf)