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Contents

README

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LR123WF270MT4E

UNI ROYAL Uniroyal Elec · Current Sense Resistors / Shunt Resistors · 2512

LR123WF270MT4E 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
Resistance tolerance (code F = ±1%) -1 1 % 2
Temperature coefficient of resistance TCR -50 50 ppm/°C t1 +25°C, t2 125°C 4
Rated power (3W variant) P 3 W 3W wattage code; rated at 70°C ambient 2
Rated ambient temperature for full rated power 70 °C Full rated power at ambient up to 70°C; derate above 70°C per figure 1 4
Short-time overload resistance change ΔR -0.5 0.5 % LR12-3W: 4 times rated power, 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°C ambient 4
High temperature exposure resistance change ΔR -1 1 % 155±2°C for 1000 h 4
Biased humidity resistance change ΔR -0.5 0.5 % 1000 h at 85°C/85%RH, 10% of operating power; measured at 24±4 h after test 4
Rapid change of temperature resistance change ΔR -0.5 0.5 % 30 min at -55°C and 30 min at 155°C; 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 % 260±5°C, held 10±1 s 4
Solderability coverage 95 % Solder 245±3°C, dwell 2~3 s; coverage of new surface 4
Dielectric withstanding limit surge current 50 mA 500 VAC applied for 1 minute 4
Reflow peak temperature (Pb-free, recommended) Tp 260 °C Recommended reflow profile, Sn96.5/Ag3/Cu0.5 solder; N2 reflow recommended 5
Allowed reflow times 2 times Recommended reflow soldering 5
Storage temperature (recommended) 15 35 °C Recommended warehouse storage 6
Storage humidity (recommended) 25 75 %RH Recommended warehouse storage 6

CAD (KiCad official)

  • Symbol: LR123WF270MT4E
  • Footprint: Resistor_SMD:R_2512_6332Metric
  • 3D model: 2512 (KiCad packages3D, STEP)
  • 3D model files: lr123wf270mt4e-etched.step / lr123wf270mt4e-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); lr123wf270mt4e.step / lr123wf270mt4e.glb are the bare package body.

Provenance

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

  • Datasheet: UNI ROYAL Uniroyal Elec datasheet (6 pp, sha256 697e24f2047069dc, 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