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LD1117AG-50-AA3-A-R

UTC Unisonic Tech · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-223

LD1117AG-50-AA3-A-R from UTC Unisonic Tech, in a SOT-223. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 GND power_in Ground reference for the regulator (GND/ADJ pin - tied to ground on fixed-voltage versions such as this 5.0V part). Quiescent current returns through this pin (typ 5 mA).
2 VOUT power_out Regulated 5.0V output (2.940V min / 3.000V typ / 3.060V max... actually 5.0V nominal for -50 suffix). Output current up to 1.0A (LD1117A). Requires an output capacitor (MLCC supported) for stability.
3 VIN power_in Unregulated input supply. Absolute max 18V, recommended operation up to 15V. For 5.0V output at 1A the input must be at least ~6.2V (dropout 1.20V typ / 1.30V max at 1A).
4 VOUT (TAB) power_out SOT-223 heat-sink tab, electrically common with pin 2 (VOUT). Should be soldered to a copper pour on the PCB to spread heat (θJC = 15 °C/W, θJA = 165 °C/W for SOT-223).

Key specifications

Parameter Value
Manufacturer UTC Unisonic Tech
Package SOT-223
Category PMIC
Pins 4

Ordering variants

Same part, different packaging or reel option.

  • LD1117AG-50-AA3-A-R
  • LD1117AG-50-AA3-A-RAB3
  • LD1117AG-50-AA3-A-RTA3
  • LD1117AG-50-AA3-A-RTF3
  • LD1117AG-50-AA3-A-RTN3
  • LD1117AG-50-AA3-A-RTND
  • LD1117AG-50-AA3-A-RTQ2
  • LD1117AG-50-AA3-A-RTQ3
  • LD1117AG-50-AA3-A-RS08

CAD (KiCad official)

  • Symbol: LD1117AG-50-AA3-A-R
  • Footprint: Package_TO_SOT_SMD:SOT-223-3_TabPin2
  • 3D model: SOT-223 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File Size Use it when
ld1117ag-50-aa3-a-r.step 64 KB You want the bare part, or you mark your own boards.
ld1117ag-50-aa3-a-r-etched.step 2.4 MB You want the part with LD1117AG-50-AA3-A-R already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 614 faces against 75 in the bare model. It survives export, section views, and rendering in any CAD tool, and it drops straight into KiCad or Fusion with no extra setup.

Provenance

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

  • Datasheet: UTC Unisonic Tech datasheet (15 pp, sha256 f7f26a117cb07dc2, retrieved 2026-08-17, tier: manufacturer)
  • Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF