# SMD1206-125

**BORN** · Resettable Fuses · 1206

SMD1206-125 from BORN, in a 1206. 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 of the non-polarized PPTC resettable fuse; the datasheet shows two tin-plated end terminals, I-hold 1.25 A and I-trip 2.50 A at 25°C (SMD1206-125/6N and /8N, Vmax 6 V and 8 Vdc). |
| 2 | 2 | passive | Second terminal of the non-polarized PPTC resettable fuse, interchangeable with the other terminal, with Imax 100 A and R1max 0.16 Ohm. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | BORN |
| Package | 1206 |
| 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 |
|---|---|---|---|---|---|---|---|
| I-trip (tripping current) | I-trip | 2.5 |  |  | A | 25℃ still air; minimum current at which device trips | 1 |
| I-hold (holding current) | I-hold |  |  | 1.25 | A | 25℃ still air; maximum current at which device does not trip | 1 |
| Imax (maximum fault current) | Imax |  |  | 100 | A | At rated voltage Vmax | 1 |
| R0 min (initial resistance, minimum) | R0 min | 0.035 |  |  | Ohm | Initial (un-soldered) state, 25℃ | 1 |
| R1 max (resistance after trip or reflow, maximum) | R1 max |  |  | 0.16 | Ohm | 25℃, one hour after tripping or 260℃ reflow for 20 s | 1 |
| Max. time to trip |  |  |  | 0.5 | s | At specified current 8.00 A, 25℃ | 1 |
| Pd (power dissipated in tripped state) | Pd |  | 0.8 |  | W | Tripped state, 25℃ still air | 1 |
| Operating temperature |  | -40 |  | 85 | °C |  | 2 |
| Maximum device surface temperature in tripped state |  |  |  | 125 | °C | Tripped state | 2 |
| Passive aging resistance change |  | -5 |  | 5 | % | +85℃, 1000 hours; typical resistance change | 2 |
| Humidity aging resistance change |  | -5 |  | 5 | % | +85℃, 85% R.H., 1000 hours; typical resistance change | 2 |
| Thermal shock resistance change |  |  | -30 |  | % | MIL-STD-202 Method 107, +85℃ to -40℃, 20 times; typical resistance change | 2 |
| Recommended hold current at ambient |  |  | 1.83 |  | A | Ambient -40℃ (thermal derating chart) | 3 |
| Recommended hold current at ambient |  |  | 1.25 |  | A | Ambient 25℃ (thermal derating chart) | 3 |
| Recommended hold current at ambient |  |  | 0.6 |  | A | Ambient 85℃ (thermal derating chart) | 3 |
| Peak / classification reflow temperature (TP) | TP |  | 260 |  | °C | Pb-free reflow; printed as 260 +0/-5 °C | 4 |

## 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 | tin | Terminal Material Tin-Plated Nickle-Copper (Solder Material: | 6 |

## CAD (KiCad official)

- Symbol: `SMD1206-125`
- Footprint: `Fuse:Fuse_1206_3216Metric`
- 3D model: 1206 (KiCad packages3D, STEP)
- 3D model files: `smd1206-125-etched.step` / `smd1206-125-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `smd1206-125.step` / `smd1206-125.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [BORN datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590921497710587904) (7 pp, sha256 `cc4500a53a54ed1e`, retrieved 2026-10-17, 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/smd1206-125-datasheet.pdf)