# LMUN2231LT1G

**LRC** · Digital Transistors · SOT-23

LMUN2231LT1G from LRC, in a SOT-23. 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 | BASE | input | Base terminal of the NPN bias-resistor transistor, with the internal input resistor R1 = 2.2 kΩ connected to it and an input voltage Vin listed as -10 V to +12 V. |
| 2 | EMITTER | passive | Emitter terminal of the NPN transistor, with emitter-base cutoff current IEBO specified at VEB = 6.0 V. |
| 3 | COLLECTOR | passive | Collector terminal of the NPN transistor, rated for VCBO = 50 V, VCEO = 50 V and a continuous collector current IC of 100 mA. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | LRC |
| Package | SOT-23 |
| Category | Transistors/Thyristors |
| 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 |
|---|---|---|---|---|---|---|---|
| DC Current Gain | HFE | 8 |  |  |  | IC = 5.0 mA, VCE = 10 V | 2 |
| Collector-Emitter Breakdown Voltage | VBR(CEO) | 50 |  |  | V | IC = 2.0 mA, IB = 0 | 2 |
| Collector-Base Breakdown Voltage | VBR(CBO) | 50 |  |  | V | IC = 10 μA, IE = 0 | 2 |
| Collector-Base Cutoff Current | ICBO |  |  | 100 | nA | VCB = 50 V, IE = 0 | 2 |
| Collector-Emitter Cutoff Current | ICEO |  |  | 500 | nA | VCE = 50 V, IB = 0 | 2 |
| Emitter-Base Cutoff Current | IEBO |  |  | 2.3 | mA | VEB = 6.0 V, IC = 0 | 2 |
| Collector-Emitter Saturation Voltage | VCE(sat) |  |  | 0.25 | V | IC = 10 mA, IB = 5 mA | 2 |
| Output Voltage (on) | VOL |  |  | 0.2 | V | VCC = 5.0 V, VB = 2.5 V, RL = 1.0KΩ | 2 |
| Output Voltage (on) | VOH | 4.9 |  |  | V | VCC = 5.0 V, VB = 0.25 V, RL = 1.0KΩ | 2 |
| Input Resistor | R1 | 1.5 |  | 2.9 | KΩ |  | 2 |
| Resistor Ratio | R1/R2 | 0.8 |  | 1.2 |  |  | 2 |
| Collector-Base Voltage | VCBO |  |  | 50 | V |  | 1 |
| Collector-Emitter Voltage | VCEO |  |  | 50 | V |  | 1 |
| Collector Current, Continuous | IC |  |  | 100 | mA |  | 1 |
| Total Device Dissipation | PD |  |  | 246 | mW | FR−5 Board (Note 1) @ TA = 25ºC | 1 |
| Junction and Storage Temperature | TJ,Tstg | -55 |  | 150 | ºC |  | 1 |
| Input Voltage | Vin | -10 |  | 12 | V |  | 1 |
| Derate above 25ºC |  |  | 1.5 |  | mW/ºC | Derate above 25ºC | 1 |
| Thermal Resistance, Junction-to-Ambient | RΘJA |  | 508 |  | ºC/W | Junction-to-Ambient (Note 1) | 1 |
| Device nominal resistor R1 | R1 |  | 2.2 |  | K |  | 1 |
| Device nominal resistor R2 | R2 |  | 2.2 |  | K |  | 1 |

## CAD (KiCad official)

- Symbol: `LMUN2231LT1G`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `lmun2231lt1g-etched.step` / `lmun2231lt1g-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lmun2231lt1g.step` / `lmun2231lt1g.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/8588946673959907328) (5 pp, sha256 `71ca714b912db648`, retrieved 2026-10-17, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-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/lmun2231lt1g-datasheet.pdf)