# FRM121WJR001TM

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

FRM121WJR001TM from FOJAN, 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 resistor; either orientation. |
| 2 | 2 | passive | Terminal 2 of an unpolarised resistor; either orientation. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | FOJAN |
| 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 |
|---|---|---|---|---|---|---|---|
| Resistance (1206 1W variant) |  |  |  | 0.2 | mΩ |  | 3 |
| Max loading current (1206 1W) |  |  |  | 70.7 | A |  | 3 |
| Resistance tolerance (code J) |  | -5 |  | 5 | % |  | 1 |
| Short-time overload resistance change |  |  |  | 0.2 | mΩ | JIS C 5201 4.13; overload power for 5 s; measure variation of resistance | 3 |
| Solderability (wetting coverage) |  | 95 |  |  | % | Flux dip, solder bath 245±5℃, 3±0.5 s | 4 |
| Resistance to soldering heat resistance change |  |  |  | 0.2 | mΩ | Flux dip, solder bath 260±5℃, 10±0.5 s | 4 |
| Rapid temperature change resistance change |  |  |  | 0.2 | mΩ | T1 -55±3℃, T2 155±3℃/125±3℃, 30 min per step, 1000 cycles | 4 |
| Terminal bending resistance change |  |  |  | 0.2 | mΩ | Board bend 5+0.2/0 mm (size 1206 or smaller), held 20±1 s | 5 |
| Load life resistance change |  |  |  | 0.2 | mΩ | 70±2℃, ON 1.5 h / OFF 0.5 h, rated voltage, 1000 +24/-0 h | 5 |
| Humidity resistance change |  |  |  | 0.2 | mΩ | 40±2℃, 90~95 %RH, rated voltage 1.5 h on / 0.5 h off, 1000 +48/-0 h | 5 |
| Rated power at 70℃ (1206 1W) |  |  | 1 |  | W | Power Rating at 70℃ | 3 |

## CAD (KiCad official)

- Symbol: `FRM121WJR001TM`
- Footprint: `Resistor_SMD:R_1206_3216Metric`
- 3D model: 1206 (KiCad packages3D, STEP)
- 3D model files: `frm121wjr001tm-etched.step` / `frm121wjr001tm-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `frm121wjr001tm.step` / `frm121wjr001tm.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [FOJAN datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8602849026480095232) (9 pp, sha256 `b57004d0e1be4765`, retrieved 2026-10-17, 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`, 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/frm121wjr001tm-datasheet.pdf)