# LMBTA42LT1G

**LRC** · Bipolar (BJT) · SOT-23

LMBTA42LT1G 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 LMBTA42LT1G NPN transistor; the datasheet gives V_BE(sat) of 0.9 Vdc max at I_C = 20 mAdc, I_B = 2.0 mAdc. |
| 2 | EMITTER | passive | Emitter terminal; the datasheet gives emitter-base voltage V_EBO of 6.0 Vdc max and emitter-base breakdown V_(BR)EBO of 6.0 Vdc min. |
| 3 | COLLECTOR | passive | Collector terminal; the datasheet gives collector-emitter voltage V_CEO of 300 Vdc for LMBTA42 and collector current I_C of 500 mAdc continuous. |

## 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 |
|---|---|---|---|---|---|---|---|
| Collector–Emitter Voltage | VCEO |  |  | 300 | Vdc |  | 1 |
| Collector–Base Voltage | VCBO |  |  | 300 | Vdc |  | 1 |
| Emitter–Base Voltage | VEBO |  |  | 6 | Vdc |  | 1 |
| Collector Current — Continuous | IC |  |  | 500 | mAdc |  | 1 |
| Junction and Storage Temperature | TJ, Tstg | -55 |  | 150 | °C |  | 1 |
| Total Device Dissipation (FR-5 Board) | PD |  |  | 225 | mW | TA = 25°C, FR-5 board | 1 |
| Thermal Resistance, Junction to Ambient (FR-5 Board) | RθJA |  |  | 556 | °C/W | FR-5 board | 1 |
| Total Device Dissipation (Alumina Substrate) | PD |  |  | 300 | mW | TA = 25°C, alumina substrate | 1 |
| Thermal Resistance, Junction to Ambient (Alumina Substrate) | RθJA |  |  | 417 | °C/W | alumina substrate | 1 |
| Collector–Emitter Breakdown Voltage | V(BR)CEO | 300 |  |  | Vdc | IC = 1.0 mAdc, IB = 0 (LMBTA42) | 1 |
| Collector–Base Breakdown Voltage | V(BR)CBO | 300 |  |  | Vdc | IC = 100 µAdc, IE = 0 (LMBTA42) | 1 |
| Emitter–Base Breakdown Voltage | V(BR)EBO | 6 |  |  | Vdc | IE = 100 µAdc, IC = 0 | 1 |
| Collector Cutoff Current | ICBO |  |  | 0.1 | µAdc | VCB = 200 Vdc, IE = 0 (LMBTA42) | 1 |
| Emitter Cutoff Current | IEBO |  |  | 0.1 | µAdc | VEB = 6.0 Vdc, IC = 0 (LMBTA42) | 1 |
| DC Current Gain | hFE | 25 |  |  |  | IC = 1.0 mAdc, VCE = 10 Vdc (Both Types) | 2 |
| DC Current Gain | hFE | 40 |  |  |  | IC = 10 mAdc, VCE = 10 Vdc (Both Types) | 2 |
| Collector–Emitter Saturation Voltage | VCE(sat) |  |  | 0.5 | Vdc | IC = 20 mAdc, IB = 2.0 mAdc (LMBTA42) | 2 |
| Base–Emitter Saturation Voltage | VBE(sat) |  |  | 0.9 | Vdc | IC = 20 mAdc, IB = 2.0 mAdc | 2 |
| Current–Gain–Bandwidth Product | fT | 50 |  |  | MHz | VCE = 20 Vdc, IC = 10 mA, f = 100 MHz | 2 |
| Collector–Base Capacitance | Ccb |  |  | 3 | pF | VCB = 20 Vdc, IE = 0, f = 1.0 MHz (LMBTA42) | 2 |

## CAD (KiCad official)

- Symbol: `LMBTA42LT1G`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `lmbta42lt1g-etched.step` / `lmbta42lt1g-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lmbta42lt1g.step` / `lmbta42lt1g.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/8586176158026616832) (4 pp, sha256 `4f28cae5709468a3`, retrieved 2026-10-09, 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/lmbta42lt1g-datasheet.pdf)