# LR431AKLT1G

**LRC** · Voltage Reference · SOT-23

LR431AKLT1G from LRC, in a SOT-23. 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 | REF | input | Reference input pin connected to internal 2.5 V error-amplifier; reference input current Iref 0.5 µA typ / 1.2 µA max (IKA = 10 mA, R1 = 10 kΩ); full-temperature deviation 0.4 µA typ / 1.2 µA max. |
| 2 | K | power_in | Cathode terminal; regulated supply node with VKA range VREF to 36 V; continuous cathode current −100 mA to +150 mA; minimum cathode current for regulation 0.08 mA typ / 0.3 mA max; dynamic impedance 0.1 Ω typ at 1 kHz. |
| 3 | A | power_in | Anode terminal; connect to circuit ground reference; all voltages and the 2.5 V internal reference are measured with respect to this pin. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | LRC |
| Package | SOT-23 |
| 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 |
|---|---|---|---|---|---|---|---|
| Reference Input Voltage 1 (0.5% grade, Vref 2.50 V class) | Vref | 2.488 | 2.5 | 2.512 | V | VKA=VREF,IKA=10mA | 2 |
| Reference Input Voltage 2 (0.5% grade, Vref 2.495 V class) | Vref | 2.483 | 2.495 | 2.507 | V | VKA=VREF,IKA=10mA | 2 |
| Deviation of reference input voltage over temperature | Vref |  | 8 | 17 | mV | VKA=VREF,IKA=10mA,TMIN to TA to TMAX | 2 |
| Ratio of change in reference input voltage to change in cathode voltage (VKA=10V to VREF) | Vref/VKA |  | -1 | -2.7 | mV/V | IKA=10mA,VKA=10V~VREF | 2 |
| Ratio of change in reference input voltage to change in cathode voltage (VKA=36V to 10V) | Vref/VKA |  | -0.4 |  | mV/V | IKA=10mA,VKA=36V~10V | 2 |
| Reference input current | Iref |  | 0.5 | 1.2 | µA | IKA=10mA,R1=10kΩ,R2= | 2 |
| Deviation of reference input current over full temperature range | Iref/T |  | 0.4 | 1.2 | µA | IKA=10mA,R1=10k,R2=,TA=full temperature range | 2 |
| Minimum cathode current for regulation | IKA(min) |  | 0.08 | 0.3 | mA | VKA=VREF | 2 |
| Off-state cathode current | IKA(OFF) |  | 0.01 | 0.8 | µA | VKA=36V,VREF=0 | 2 |
| Dynamic impedance | ZKA |  | 0.1 | 0.37 | Ω | VKA=VREF,IKA=0.2 to 100mA,f1.0kHz | 2 |
| Cathode current (continuous) recommended range | IKA |  |  | 100 | mA |  | 2 |
| Operating ambient temperature range (classification table) | Topr | -40 |  | 125 | °C |  | 2 |
| Cathode current range (continuous) | IKA | -100 |  | 150 | mA |  | 2 |
| Reference input current range | Iref | -0.05 |  | 10 | mA |  | 2 |
| Operating junction temperature | Tj |  |  | 150 | °C |  | 2 |
| Storage temperature | Tstg | -65 |  | 150 | °C |  | 2 |
| Thermal resistance, junction to ambient | θJA |  |  | 206 | °C/W |  | 2 |

## CAD (KiCad official)

- Symbol: `LR431AKLT1G`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `lr431aklt1g-etched.step` / `lr431aklt1g-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lr431aklt1g.step` / `lr431aklt1g.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [LRC datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588948145267359744) (5 pp, sha256 `2af43aa6be3e061f`, retrieved 2026-09-22, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.2`, primary `claude-haiku-4-5-20251001` (text), consensus `claude-sonnet-4-6` (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/lr431aklt1g-datasheet.pdf)