# LD1117S33CTR

**STMicroelectronics** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-223-4

LD1117S33CTR from STMicroelectronics, 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 | Device ground / common reference. Also carries the internal adjust/reference return current. |
| 2 | VOUT | power_out | Regulated 3.3 V output, up to 800 mA. Requires a minimum 10 µF capacitor to ground for stability. The exposed SOT-223 tab is internally connected to this pin. |
| 3 | VIN | power_in | Unregulated input supply. Absolute max 15 V DC (18 V when IOUT < 20 mA). A 100 nF input capacitor is recommended near the pin. |
| 4 | TAB | passive | SOT-223 heat-sink tab, internally tied to VOUT. Solder to a copper pour for thermal dissipation; the pour is at VOUT potential. |

## Key specifications

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

## Ordering variants

Same part, different packaging or reel option.

- `LD1117S33CTR`
- `LD1117S33CTRV33`
- `LD1117S33CTRV33C`
- `LD1117S33CTRDT33`
- `LD1117S33CTRDT33TR`
- `LD1117S33CTRD33`
- `LD1117S33CTRD33TR`

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Output voltage (VIN=5.3 V, IO=10 mA, TJ=25 °C) | VO | 3.24 | 3.3 | 3.36 | V | Vin = 5.3 V, IO = 10 mA, TJ = 25 °C | 18 |
| Output voltage (full load and line range) | VO | 3.16 |  | 3.44 | V | IO = 0 to 800 mA, Vin = 4.75 to 10 V | 18 |
| Line regulation | ΔVO |  | 1 | 30 | mV | Vin = 4.75 to 15 V, IO = 0 mA | 18 |
| Load regulation | ΔVO |  | 1 | 30 | mV | Vin = 4.75 V, IO = 0 to 800 mA | 18 |
| Operating input voltage | Vin |  |  | 15 | V | IO = 100 mA | 18 |
| Quiescent current | Id |  | 5 | 10 | mA | Vin ≤ 15 V | 18 |
| Output current | IO | 800 | 950 | 1300 | mA | Vin = 8.3 V, TJ = 25 °C | 18 |
| Supply voltage rejection | SVR | 60 | 75 |  | dB | IO = 40 mA, f = 120 Hz, TJ = 25 °C, Vin = 6.3 V, Vripple = 1 VPP | 18 |
| Dropout voltage | Vd |  | 1 | 1.1 | V | IO = 100 mA, TJ = 0 to 125 °C | 18 |
| Dropout voltage | Vd |  | 1.05 | 1.15 | V | IO = 500 mA, TJ = 0 to 125 °C | 18 |
| Dropout voltage | Vd |  | 1.1 | 1.2 | V | IO = 800 mA, TJ = 0 to 125 °C | 18 |
| Dropout voltage | Vd |  |  | 1.1 | V | IO = 100 mA | 18 |
| Dropout voltage | Vd |  |  | 1.2 | V | IO = 500 mA | 18 |
| Dropout voltage | Vd |  |  | 1.3 | V | IO = 800 mA | 18 |
| Temperature stability | ΔVO |  |  | 0.5 | % |  | 18 |
| Long term stability | ΔVO |  |  | 0.3 | % | 1000 hrs, TJ = 125 °C | 18 |
| Thermal regulation |  |  | 0.01 | 0.1 | %/W | Ta = 25 °C, 30 ms Pulse | 18 |
| DC input voltage | VIN |  |  | 15 | V |  | 7 |
| DC input voltage (footnote 1) | VIN |  |  | 18 | V | IOUT lower than 20 mA | 7 |
| Power dissipation | PTOT |  |  | 12 | W |  | 7 |
| Storage temperature range | TSTG | -40 |  | 150 | °C |  | 7 |
| Operating junction temperature range (C version) | TOP | -40 |  | 125 | °C | for C version | 7 |
| Thermal resistance junction-case (SOT-223) | RthJC |  | 15 |  | °C/W | SOT-223 | 7 |
| Thermal resistance junction-ambient (SOT-223) | RthJA |  | 110 |  | °C/W | SOT-223 | 7 |

## CAD (KiCad official)

- Symbol: `LD1117S33CTR`
- Footprint: `Package_TO_SOT_SMD:SOT-223`
- 3D model: SOT-223-4 (KiCad packages3D, STEP)
- 3D model files: `ld1117s33ctr-etched.step` / `ld1117s33ctr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ld1117s33ctr.step` / `ld1117s33ctr.glb` are the bare package body.

## 3D model downloads

Two STEP files. Same geometry, different body top:

| File | Size | Use it when |
|---|---|---|
| [`ld1117s33ctr.step`](ld1117s33ctr.step) | 64 KB | You want the bare part, or you mark your own boards. |
| [`ld1117s33ctr-etched.step`](ld1117s33ctr-etched.step) | 2.0 MB | You want the part with `LD1117S33CTR` already on it. |

The marking in the etched file is real recessed geometry cut into the solid, not a
texture or a decal: 495 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:** [STMicroelectronics datasheet](https://www.st.com/resource/en/datasheet/ld1117s33ctr.pdf) (44 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](docs/ld1117s33ctr-datasheet.pdf)