# LRAN12CFTR039

**NCT** · Current Sense Resistors/Shunt Resistors · 1206

LRAN12CFTR039 from NCT, 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 | First terminal electrode of the 2-terminal LRAN12 alloy current-sense resistor (3.2 x 1.6 mm body), rated 1 W for 1 mΩ to 39 mΩ and max rated current 31.62 A; the datasheet does not mark which end is pin 1 and the part is non-polarized. |
| 2 | 2 | passive | Second terminal electrode of the 2-terminal LRAN12 alloy current-sense resistor, with resistance measured 4-wire at the back electrodes and rated power derated above 70 °C to zero at 170 °C. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | NCT |
| Package | 1206 |
| Category | Resistors |
| 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 |
|---|---|---|---|---|---|---|---|
| Insulation resistance |  | 100 |  |  | MΩ | 100 VDC applied 1 min between electrodes and protective layer / substrate | 9 |
| Resistance tolerance |  | -1 |  | 1 | % | Tolerance code F (1%) per part-numbering table | 3 |
| Nominal resistance | R |  | 39 |  | mΩ | Part code R039; 4-wire measurement at back electrodes | 3 |
| Temperature coefficient of resistance | TCR | -50 |  | 50 | ppm/°C | Per TCR test: R1 at room temperature, R2 at 125 °C | 4 |
| Rated power |  |  |  | 1 | W | 1W row (1mΩ~39mΩ); derate above 70 °C per curve | 4 |
| Maximum rated current |  |  |  | 31.62 | A | 1W row, which covers 1mΩ~39mΩ; printed value applies to the row | 4 |
| Maximum overload current |  |  |  | 70.71 | A | 1W row, which covers 1mΩ~39mΩ; printed value applies to the row | 4 |
| Operating temperature range |  | -55 |  | 170 | °C |  | 4 |
| Short time overload resistance change | ΔR/R | -0.5 |  | 0.5 | % | 5 s at 5x rated power, then 24 h rest | 8 |
| Biased humidity resistance change | ΔR/R | -0.5 |  | 0.5 | % | 85 °C, 85 %RH, rated current, 90 min ON / 30 min OFF, 1000 h | 8 |
| Temperature cycling resistance change | ΔR/R | -0.5 |  | 0.5 | % | -55 °C to +125 °C, 1000 cycles | 8 |
| Low temperature exposure resistance change | ΔR/R | -0.5 |  | 0.5 | % | -55 °C, 1000 h | 8 |
| High temperature exposure resistance change | ΔR/R | -1 |  | 1 | % | 170 °C, 1000 h | 9 |
| Load life resistance change | ΔR/R | -1 |  | 1 | % | 70 °C, rated current, 90 min ON / 30 min OFF, 1000 h | 9 |
| Resistance to solder heat resistance change | ΔR/R | -0.5 |  | 0.5 | % | 260 °C solder bath, 10 s | 9 |
| Resistance to solvent resistance change | ΔR/R | -0.5 |  | 0.5 | % | Isopropanol, 20-25 °C, 60 s | 9 |
| Joint strength of solder resistance change | ΔR/R | -0.5 |  | 0.5 | % | Bend test on solder joint test board | 9 |

## CAD (KiCad official)

- Symbol: `LRAN12CFTR039`
- Footprint: `Resistor_SMD:R_1206_3216Metric`
- 3D model: 1206 (KiCad packages3D, STEP)
- 3D model files: `lran12cftr039-etched.step` / `lran12cftr039-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lran12cftr039.step` / `lran12cftr039.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [NCT datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590299007064182784) (12 pp, sha256 `9468aafd42725899`, retrieved 2026-11-07, tier: lcsc)
- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- **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/lran12cftr039-datasheet.pdf)