# LR122WF700MT4E

**UNI-ROYAL(Uniroyal Elec)** · Current Sense Resistors / Shunt Resistors · 2512

LR122WF700MT4E from UNI-ROYAL(Uniroyal Elec), in a 2512. 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 | UNI-ROYAL(Uniroyal Elec) |
| Package | 2512 |
| 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 |
|---|---|---|---|---|---|---|---|
| Temperature coefficient (TCR) | TCR | -50 |  | 50 | ppm/°C | t1=+25°C, t2=125°C | 4 |
| Resistance tolerance |  | -1 |  | 1 | % | F = ±1% (7th code of part number) | 2 |
| Short-time overload resistance change | ΔR | -0.5 |  | 0.5 | % | 5 times rated power for LR12-2W, 5 seconds | 4 |
| Load life resistance change | ΔR | -1 |  | 1 | % | 1000 h at rated or max working current (whichever less), 1.5 h ON / 0.5 h OFF, 70±2℃ ambient | 4 |
| High temperature exposure resistance change | ΔR | -1 |  | 1 | % | 155±2℃ for 1000 H (MIL-STD-202 108A) | 4 |
| Biased humidity resistance change | ΔR | -0.5 |  | 0.5 | % | 1000 h, 85℃/85%RH, 10% of operating power | 4 |
| Rapid change of temperature resistance change | ΔR | -0.5 |  | 0.5 | % | 30 min at -55℃ and 30 min at 155℃; 100 cycles | 4 |
| Terminal bending resistance change | ΔR | -0.5 |  | 0.5 | % | 2 mm, 10 s | 4 |
| Resistance to solder heat resistance change | ΔR | -0.5 |  | 0.5 | % | Dip at 260±5℃ held 10±1 seconds | 4 |
| Solderability coverage |  | 95 |  |  | % | Solder 245±3℃, dwell 2~3 seconds; coverage of new surface | 4 |
| Surge current limit (dielectric withstanding test) |  |  |  | 50 | mA | Applied 500 VAC for 1 minute | 4 |
| Rated power | P |  | 2 |  | W | LR12 2W rating, continuous load at 70℃ ambient | 2 |
| Nominal resistance (decoded from part number) | R |  | 70 |  | mΩ | Part number codes 8th-11th = 700, M (10^-4) = 0.07 Ω | 2 |
| Ambient temperature for rated power |  |  |  | 70 | ℃ | Continuous load; derate above 70℃ per Figure 1 | 3 |
| Recommended storage temperature |  | 15 |  | 35 | ℃ | Recommended warehouse storage | 7 |
| Recommended storage humidity |  | 25 |  | 75 | %RH | Recommended warehouse storage | 7 |
| Reflow temperature Tp (peak) | Tp |  |  | 260 | ℃ | Pb-free reflow profile; time within +0/-5℃ of peak 10 s | 5 |
| Reflow time above liquidus | TL | 217 |  |  | ℃ | Time above TL 60-150 seconds | 5 |
| Reflow ramp-up rate |  |  |  | 3 | ℃/s | Average, Ts max to Tp | 5 |
| Reflow ramp-down rate |  |  |  | 6 | ℃/s | Ramp-down from peak | 5 |
| Allowed reflow cycles |  |  |  | 2 | times | Reflow soldering | 5 |

## CAD (KiCad official)

- Symbol: `LR122WF700MT4E`
- Footprint: `Resistor_SMD:R_2512_6332Metric`
- 3D model: 2512 (KiCad packages3D, STEP)
- 3D model files: `lr122wf700mt4e-etched.step` / `lr122wf700mt4e-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lr122wf700mt4e.step` / `lr122wf700mt4e.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [UNI-ROYAL(Uniroyal Elec) datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8603144027294752768) (7 pp, sha256 `e01cdf7929676065`, retrieved 2026-10-17, 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/lr122wf700mt4e-datasheet.pdf)