# LM317MDT-MS

**MSKSEMI** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · TO-252

LM317MDT-MS from MSKSEMI, in a TO-252. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | ADJ | input | Adjust pin (Vadj) connected to the internal 1.25V reference; adjustable pin current is 46 µA typical and 100 µA maximum. |
| 2 | OUT | power_out | Regulated output, adjustable from 1.2 to 37V and supplying more than 1.5A of load current with internal current limiting and thermal shutdown. |
| 3 | IN | power_in | Unregulated input voltage; the input-output voltage differential must not exceed 40V. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | MSKSEMI |
| Package | TO-252 |
| Category | Power Management (PMIC) |
| Pins | 3 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Input-Output Voltage Differential | VI-VO |  |  | 40 | V |  | 3 |
| Lead Temperature | TLEAD |  |  | 230 | ℃ |  | 3 |
| Operating Junction Temperature Range | TJ | 0 |  | 125 | ℃ |  | 3 |
| Storage Temperature Range | Tstg | -55 |  | 125 | ℃ |  | 3 |
| Temperature Coefficient of Output Voltage | ΔVO/ΔT | -0.02 |  | 0.02 | %/℃ |  | 3 |
| Line Regulation | Rline |  | 0.01 | 0.04 | %/V | TA=25℃, 3V≤VI-VO≤40V | 3 |
| Line Regulation | Rline |  | 0.02 | 0.07 | %/V | 3V≤VI-VO≤40V | 3 |
| Load Regulation | Rload |  | 18 | 25 | mV | TA=25℃, 10mA≤IO≤IMAX, VO<5V | 3 |
| Load Regulation | Rload |  | 0.4 | 0.5 | %VO | TA=25℃, 10mA≤IO≤IMAX, VO≥5V | 3 |
| Load Regulation | Rload |  | 40 | 70 | mV | 10mA≤IO≤IMAX, VO<5V | 3 |
| Load Regulation | Rload |  | 0.8 | 1.5 | %VO | 10mA≤IO≤IMAX, VO≥5V | 3 |
| Adjustable Pin Current | ADJ |  | 46 | 100 | µA |  | 3 |
| Adjustable Pin Current Change | ΔlADJ |  | 2 | 5 |  | 3V≤VI-VO≤40V, 10mA≤IO≤IMAX, PD≤PMAX | 3 |
| Reference Voltage | VREF | 1.2 | 1.25 | 1.3 | V | 3V≤VIN-VO≤40V, 10mA≤IO≤IMAX, PD≤PMAX | 3 |
| Temperature Stability | STT |  | 0.7 |  | %/ VO |  | 3 |
| Minimum Load Current to Maintain Regulation | IL(MIN) |  | 3.5 | 12 | mA | VI-VO=40V | 3 |
| RMS Noise, % of VOUT | N |  | 0.003 | 0.01 | %/ VO | TA=25℃, 10Hz≤f≤10KHz | 3 |
| Long-Term Stability | ST |  | 0.3 | 1 | % | TJ=THIGH; TA=25℃ for end point mesasurements, 1000 HR | 3 |
| Thermal Resistance Junction to Case | RθJC |  | 5 |  | ℃/W |  | 3 |

## CAD (KiCad official)

- Symbol: `LM317MDT-MS`
- Footprint: `Package_TO_SOT_SMD:TO-252-2`
- 3D model: TO-252 (KiCad packages3D, STEP)
- 3D model files: `lm317mdt-ms-etched.step` / `lm317mdt-ms-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lm317mdt-ms.step` / `lm317mdt-ms.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [MSKSEMI datasheet](docs/lm317mdt-ms-datasheet.pdf) (7 pp, sha256 `bd35eea1daa65338`, retrieved 2026-11-04, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (text+vision), consensus `claude-opus-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/lm317mdt-ms-datasheet.pdf)