# L78M12ACDT-TR

**STMicroelectronics** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · TO-252-2(DPAK)

L78M12ACDT-TR from STMicroelectronics, in a TO-252-2(DPAK). 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 | INPUT | power_in | Unregulated DC input supply. Absolute maximum V_I = 35 V (for V_O up to 18 V). Requires a 0.33 µF input bypass capacitor if the regulator is located far from the power-supply filter. |
| 2 | GND | power_in | Common ground reference for input and output. Electrically connected to the exposed DPAK tab (thermal pad) which serves as the primary heatsink connection. |
| 3 | OUTPUT | power_out | Regulated +12 V output, 500 mA capable. V_O typ = 12 V (11.75 to 12.25 V at T_J = 25 °C). A 0.1 µF output capacitor improves transient response. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | STMicroelectronics |
| Package | TO-252-2(DPAK) |
| Category | PMIC |
| Pins | 3 |

## Ordering variants

Same part, different packaging or reel option.

- `L78M12ACDT-TR`

## CAD (KiCad official)

- Symbol: `L78M12ACDT-TR`
- Footprint: `Package_TO_SOT_SMD:TO-252-2`
- 3D model: TO-252-2(DPAK) (KiCad packages3D, STEP)
- 3D model files: `l78m12acdt-tr-etched.step` / `l78m12acdt-tr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `l78m12acdt-tr.step` / `l78m12acdt-tr.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [STMicroelectronics datasheet](https://www.st.com/resource/en/datasheet/l78m12acdt-tr.pdf) (29 pp, sha256 `06d79d9f1c19140c`, 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/l78m12acdt-tr-datasheet.pdf)