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LD1117AG-33-AA3-A-R

UTC Unisonic Tech · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-223-4

LD1117AG-33-AA3-A-R from UTC Unisonic Tech, in a SOT-223-4. 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 return. For the fixed 3.3V version this pin is the device ground reference. Per Pin Assignment code 'A' (AA3 = SOT-223): pin 1 = G (GND/ADJ).
2 VOUT power_out Regulated output. Fixed 3.3V nominal, up to 1A (LD1117A variant). Requires an output capacitor for stability; MLCC supported. Also connected internally to the SOT-223 tab (pin 4).
3 VIN power_in Unregulated input supply. Absolute maximum 18V, recommended operating input voltage 15V max. Dropout typically 1.15V at 500mA, 1.20V at 1A.
4 VOUT power_out SOT-223 thermal tab, internally connected to VOUT (pin 2). Solder to a copper pour on the PCB to improve thermal dissipation (θJA = 165 °C/W in SOT-223).

Key specifications

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

Ordering variants

Same part, different packaging or reel option.

  • LD1117AG-33-AA3-A-R
  • LD1117AG-33-AA3-A-RAB3
  • LD1117AG-33-AA3-A-RTA3
  • LD1117AG-33-AA3-A-RTF3
  • LD1117AG-33-AA3-A-RTN3
  • LD1117AG-33-AA3-A-RTND
  • LD1117AG-33-AA3-A-RT2Q
  • LD1117AG-33-AA3-A-RTQ2
  • LD1117AG-33-AA3-A-RTQ3
  • LD1117AG-33-AA3-A-RS08

CAD (KiCad official)

  • Symbol: LD1117AG-33-AA3-A-R
  • Footprint: Package_TO_SOT_SMD:SOT-223
  • 3D model: SOT-223-4 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File Size Use it when
ld1117ag-33-aa3-a-r.step 64 KB You want the bare part, or you mark your own boards.
ld1117ag-33-aa3-a-r-etched.step 2.5 MB You want the part with LD1117AG-33-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: 634 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