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LD1117STR

STMicroelectronics · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-223-3

LD1117STR from STMicroelectronics, in a SOT-223-3. 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 ADJ input Adjust pin. Sets output voltage via external resistor divider between OUT and ADJ. Reference voltage between OUT and ADJ is 1.25 V typ. (1.225-1.275 V). Adjustment pin current (IADJ) is 60 µA typ., 120 µA max. On fixed-voltage variants this pin is GND instead.
2 VOUT power_out Regulated output voltage. Adjustable from 1.25 V to 15 V via R1/R2 divider. Delivers up to 800 mA (min) / 950 mA (typ) with VIN-VOUT = 5 V at TJ = 25 °C. Requires 10 µF minimum output capacitor for stability. Tab (pin 4) is internally connected to this pin.
3 VIN power_in Unregulated DC input. Operating input voltage up to 15 V (18 V absolute max for IOUT < 20 mA). Dropout voltage 1 V typ. (1.1 V max at 100 mA, 1.15 V at 500 mA, 1.2 V at 800 mA). 100 nF input decoupling capacitor recommended.
4 TAB power_out Metal heat-sink tab, internally connected to VOUT. Used for thermal dissipation to PCB copper pour. RthJC = 15 °C/W, RthJA = 110 °C/W for SOT-223.

Key specifications

Parameter Value
Manufacturer STMicroelectronics
Package SOT-223-3
Category PMIC
Pins 4

Ordering variants

  • LD1117STR
  • LD1117STRSC-R
  • LD1117STRD33TR
  • LD1117STRD33CTR
  • LD1117STRDTTR
  • LD1117STRDTC-R
  • LD1117STRV
  • LD1117STRV-DG

CAD (KiCad official)

  • Symbol: LD1117STR
  • Footprint: Package_TO_SOT_SMD:SOT-223-3_TabPin2
  • 3D model: SOT-223-3 (KiCad packages3D, STEP)

Provenance

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

  • Datasheet: STMicroelectronics datasheet (None pp, sha256 1b80923ec6ca9161, 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

Symbol & Footprint

Schematic Symbol

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PCB Footprint

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