# MSMD200

**KUU** · Resettable Fuses · 1812

MSMD200 from KUU, 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 | KUU |
| 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 |
|---|---|---|---|---|---|---|---|
| Minimum resistance prior to trip | R min | 0.02 |  |  | Ω | 25℃, prior to trip | 1 |
| Maximum resistance one hour post reflow | R1max |  |  | 0.08 | Ω | 25℃, measured one hours post reflow | 1 |
| Minimum tripping current | IT | 4 |  |  | A | 25℃ still air | 1 |
| Maximum holding current | IH |  |  | 2 | A | 25℃ still air | 1 |
| Maximum voltage withstand at rated current | Vmax |  |  | 16 | V | at rated current | 1 |
| Maximum fault current withstand at rated voltage | I max |  |  | 100 | A | at rated voltage | 1 |
| Maximum time to trip | Ttrip |  |  | 3 | s | at 8.0 A | 1 |
| Rated working power | Pd typ |  | 1.2 |  | W |  | 1 |
| Maximum hold current at 85℃ ambient |  |  |  | 1.25 | A | maximum ambient operating temperature 85℃ (thermal derating table) | 1 |
| Maximum hold current at -40℃ ambient |  |  |  | 3.08 | A | ambient -40℃ (thermal derating table) | 1 |
| Minimum trip current at 85℃ ambient |  | 2.5 |  |  | A | ambient 85℃ (thermal derating table) | 1 |
| Minimum trip current at -40℃ ambient |  | 6.16 |  |  | A | ambient -40℃ (thermal derating table) | 1 |
| Maximum ambient operating temperature range |  | -40 |  | 85 | ℃ | thermal derating table range | 1 |
| Average ramp-up rate |  |  |  | 3 | ℃/second | solder reflow profile | 1 |
| Ramp-down rate |  |  |  | 6 | ℃/second | solder reflow profile | 1 |
| Peak reflow temperature |  |  |  | 260 | ℃ | solder reflow profile peak | 1 |
| Time above critical zone |  | 60 |  | 150 | s | critical zone above 217℃ | 1 |
| Preheat time |  | 60 |  | 180 | s | preheat 150℃ to 200℃ | 1 |
| Time from 25℃ to peak |  |  |  | 8 | minutes | solder reflow profile | 1 |

## CAD (KiCad official)

- Symbol: `MSMD200`
- 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: `msmd200-etched.step` / `msmd200-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `msmd200.step` / `msmd200.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [KUU datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8589837242836955136) (1 pp, sha256 `34b590649b58d232`, retrieved 2026-10-14, 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/msmd200-datasheet.pdf)