# S1206-FC-4.0A

**SART Nanjing Sart Tech** · Disposable Fuses · 1206

S1206-FC-4.0A from SART Nanjing Sart Tech, 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 | Terminal 1 of an unpolarised fuse; either orientation. |
| 2 | 2 | passive | Terminal 2 of an unpolarised fuse; either orientation. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | SART Nanjing Sart Tech |
| 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 |
|---|---|---|---|---|---|---|---|
| Opening time at 100% of rated current (no fusing) |  | 4 |  |  | h | 100% of current rating, no fusing | 3 |
| Opening time at 350% of rated current |  |  |  | 5 | s | 350% of current rating | 3 |
| Opening time at 1000% of rated current |  | 0.1 |  |  | ms | 1000% of current rating | 3 |
| Voltage drop (2.0A~5.0A rating) |  |  |  | 300 | mV | 100% of current rating; 2.0A~5.0A | 4 |
| Voltage drop deviation between mean values |  |  |  | 15 | % | 100% of current rating | 4 |
| Endurance: resistance change | /ΔR/ |  |  | 10 | % | 100 cycles of 1In for 1 hour ON, 15 min OFF, then 1 hour of 1.25In | 4 |
| Endurance: temperature rise | ΔT |  |  | 75 | ℃ | 100 cycles of 1In for 1 hour ON, 15 min OFF, then 1 hour of 1.25In | 4 |
| Solderability coverage |  | 95 |  |  | % | 235℃±5℃, 5sec±0.5sec | 4 |
| Resistance to soldering: resistance change | /ΔR/ |  |  | 10 | % | 260℃±5℃, 10sec±0.5sec | 4 |
| Bending test: resistance change | /ΔR/ |  |  | 10 | % | Distance between holding points 90mm; bending 2mm, time 60sec | 4 |
| High temperature operating life: resistance change | /ΔR/ |  |  | 10 | % | T=125℃±2℃, 60%In, 1000 hours; no fusing | 4 |
| Humidity (steady state): resistance change | /ΔR/ |  |  | 10 | % | T=85℃±2℃, 85%RH, 1000 hours | 4 |
| Low temperature storage: resistance change | /ΔR/ |  |  | 10 | % | T=-55℃±3℃, 96 hours | 4 |
| High temperature storage: resistance change | /ΔR/ |  |  | 10 | % | T=125℃±2℃, 1000 hours | 4 |
| Salt spray: resistance change | /ΔR/ |  |  | 10 | % | 5% salt solution, 96 hours | 4 |
| Thermal shock: resistance change | /ΔR/ |  |  | 10 | % | 100 cycles between -65℃/+125℃, 60 minutes each extreme | 5 |
| Moisture resistance: resistance change | /ΔR/ |  |  | 10 | % | 10 cycles between the specified humidity, 24 hours each cycle | 5 |
| Terminal strength: resistance change | /ΔR/ |  |  | 10 | % | Side thrust 17.7N, time 60sec | 5 |
| Mechanical shock: resistance change | /ΔR/ |  |  | 10 | % | Pulse acceleration 1000m/s2, time 6 millisecond, 18 times | 5 |
| Vibration: resistance change | /ΔR/ |  |  | 10 | % | 10Hz~2000Hz, displacement amplitude 0.75mm, acceleration 150m/s2, 12 hours | 5 |
| Infrared reflow temperature |  |  |  | 260 | ℃ | Infrared reflow | 5 |
| Infrared reflow time |  |  |  | 5 | s | Infrared reflow | 5 |
| Wave soldering reservoir temperature |  |  |  | 260 | ℃ | Wave soldering | 5 |
| Wave soldering time in reservoir |  |  |  | 10 | s | Wave soldering | 5 |
| Hand soldering temperature |  |  |  | 350 | ℃ | Hand soldering | 5 |
| Hand soldering time |  |  |  | 5 | s | Hand soldering | 5 |
| Average ramp-up rate (Tsmax to Tp) |  |  |  | 3 | ℃/sec | Pb-free assembly reflow profile | 5 |
| Preheat temperature (Tsmin to Tsmax) |  | 150 |  | 200 | ℃ | Pb-free assembly reflow profile | 5 |
| Preheat time (tsmin to tsmax) |  | 60 |  | 120 | s | Pb-free assembly reflow profile | 5 |
| Melting tin time (tL) | tL | 60 |  | 150 | s | Pb-free assembly reflow profile | 5 |
| Ramp-down rate |  |  |  | 6 | ℃/sec | Pb-free assembly reflow profile | 5 |
| Time 25℃ to peak temperature |  |  |  | 8 | min | Pb-free assembly reflow profile | 5 |
| Operating temperature |  | -55 |  | 125 | ℃ |  | 1 |
| Recommended storage ambient temperature |  | 5 |  | 30 | ℃ | Storage | 6 |
| Recommended storage relative humidity |  | 25 |  | 60 | %RH | Storage | 6 |
| Voltage rating |  |  |  | 100 | V |  | 1 |
| Interrupting rating |  |  |  | 50 | A | 100V DC, without permanent arcing, ignition and bursting of fuse link | 1 |
| Current rating |  |  | 4 |  | A |  | 1 |
| Typical cold DCR |  |  | 31 |  | mΩ | Measured at ≤10% rated current and 25℃; resistance test on coating surface | 1 |
| Typical melting I²T | I²t |  | 0.48 |  | A²s | Melting I²T at 10 times of rated current | 1 |

## CAD (KiCad official)

- Symbol: `S1206-FC-4.0A`
- Footprint: `Fuse:Fuse_1206_3216Metric`
- 3D model: 1206 (KiCad packages3D, STEP)
- 3D model files: `s1206-fc-4-0a-etched.step` / `s1206-fc-4-0a-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `s1206-fc-4-0a.step` / `s1206-fc-4-0a.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [SART Nanjing Sart Tech datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590228672482746368) (6 pp, sha256 `245a6bbea43c2eb1`, retrieved 2026-10-20, 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/s1206-fc-4-0a-datasheet.pdf)