# TL431L

**Slkor(SLKORMICRO Elec.)** · Voltage Reference · TO-92

TL431L from Slkor(SLKORMICRO Elec.), in a TO-92. 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 | REFERENCE | input | Reference input of the adjustable shunt regulator; the datasheet gives a reference input voltage of 2.475 V min, 2.5 V typ and 2.525 V max at VKA=VREF, IKA=10 mA, and a reference input current range of 0.05 to 10 mA. |
| 2 | ANODE | power_in | Anode terminal of the shunt regulator, normally connected to ground, with a cathode current range of -100 to +150 mA continuous. |
| 3 | CATHODE | passive | Cathode terminal of the shunt regulator, with a maximum cathode voltage of 36 V and a cathode current range of -100 to +150 mA continuous. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Slkor(SLKORMICRO Elec.) |
| Package | TO-92 |
| 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 |
|---|---|---|---|---|---|---|---|
| Cathode voltage | VKA |  |  | 36 | V |  | 2 |
| Cathode current range (continuous) | IKA | -100 |  | 150 | mA |  | 2 |
| Reference input current range | Iref | 0.05 |  | 10 | mA |  | 2 |
| Operating junction temperature | TJ | -40 |  | 125 | °C |  | 2 |
| Storage temperature range | TSTG | -65 |  | 150 | °C |  | 2 |
| Reference input voltage | Vref | 2.4 | 2.5 | 2.5 | V | VKA=VREF, IKA=10mA | 2 |
| Deviation of reference input voltage over temperature | ΔVref/ΔT |  | 4.5 | 17 | mV | VKA=VREF, IKA=10mA | 2 |
| Ratio of change in reference input voltage to change in cathode voltage (VKA=10V to VREF) | ΔVref/ΔVKA |  | -1 | -2.7 | V/V | ΔVKA=10V~VREF | 2 |
| Change in reference input voltage to change in cathode voltage (VKA=36V to 10V) | ΔVref/ΔVKA |  | -0.5 | -2 | V/V | IKA=10mA, ΔVKA=36V~10V | 2 |
| Reference input current | Iref |  | 1.5 | 4 | µA | IKA=10mA, R1=10kΩ | 2 |
| Deviation of reference input current over full temperature range | Δlref/ΔT |  | 0.4 | 1.2 | µA | IKA=10mA, R1=10kΩ | 2 |
| Minimum cathode current for regulation | IKA(min) |  | 0.45 | 1 | mA | VKA=VREF | 2 |
| Off-state cathode current | IKA(OFF) |  | 0.05 | 1 | µA | VKA=36V, VREF=0 | 2 |
| Dynamic impedance | ZKA |  | 0.15 | 0.5 | Ω | VKA=VREF, IKA=1 to 100mA, f≤1.0 kHz | 2 |
| Power dissipation (TO-92) | PD |  |  | 770 | mW | TO-92 column | 2 |
| Thermal resistance from junction to ambient (TO-92) | RθJA |  | 162 |  | °C/W | TO-92 column | 2 |

## CAD (KiCad official)

- Symbol: `TL431L`
- Footprint: `Package_TO_SOT_THT:TO-92_Inline`
- 3D model: TO-92 (KiCad packages3D, STEP)
- 3D model files: `tl431l-etched.step` / `tl431l-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `tl431l.step` / `tl431l.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Slkor(SLKORMICRO Elec.) datasheet](docs/tl431l-datasheet.pdf) (7 pp, sha256 `2d18cd6ce2af8ab3`, retrieved 2026-11-04, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (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/tl431l-datasheet.pdf)