# BSS138BK

**Nexperia** · MOSFETs · SOT-23

BSS138BK from Nexperia, 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 | G | input | Gate control terminal; gate-source voltage range -20 V to +20 V |
| 2 | S | passive | Source terminal of the N-channel MOSFET |
| 3 | D | passive | Drain terminal; maximum drain-source voltage 60 V, maximum drain current 360 mA at VGS = 10 V and Tamb = 25 °C |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Nexperia |
| 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 |
|---|---|---|---|---|---|---|---|
| Drain-source voltage | VDS |  |  | 60 | V | Tj = 25 °C | 3 |
| Gate-source voltage | VGS | -20 |  | 20 | V |  | 3 |
| Drain current | ID |  |  | 360 | mA | VGS = 10 V; Tamb = 25 °C; footnote [1] | 3 |
| Drain current | ID |  |  | 230 | mA | VGS = 10 V; Tamb = 100 °C; footnote [1] | 3 |
| Peak drain current | IDM |  |  | 1.2 | A | Tamb = 25 °C; single pulse; tp ≤ 10 µs | 3 |
| Total power dissipation | Ptot |  |  | 350 | mW | Tamb = 25 °C; footnote [2] | 3 |
| Total power dissipation | Ptot |  |  | 420 | mW | footnote [1] | 3 |
| Total power dissipation | Ptot |  |  | 1140 | mW | Tsp = 25 °C | 3 |
| Junction temperature | Tj | -55 |  | 150 | °C |  | 3 |
| Ambient temperature | Tamb | -55 |  | 150 | °C |  | 3 |
| Storage temperature | Tstg | -65 |  | 150 | °C |  | 3 |
| Source current (source-drain diode) | IS |  |  | 360 | mA | Tamb = 25 °C; footnote [1] | 3 |
| Electrostatic discharge voltage | VESD |  |  | 1500 | V | HBM; footnote [3]: measured between all pins | 3 |
| Thermal resistance junction to ambient | Rth(j-a) |  | 310 | 370 | K/W | in free air; footnote [1]: FR4 PCB, single-sided copper, tin-plated, standard footprint | 4 |
| Thermal resistance junction to ambient | Rth(j-a) |  | 260 | 300 | K/W | footnote [2]: FR4 PCB, mounting pad for drain 1 cm2 | 4 |
| Thermal resistance junction to solder point | Rth(j-sp) |  |  | 115 | K/W |  | 4 |
| Drain-source breakdown voltage | V(BR)DSS | 60 |  |  | V | ID = 250 µA; VGS = 0 V; Tj = 25 °C | 6 |
| Gate-source threshold voltage | VGSth | 0.48 | 1.1 | 1.6 | V | ID = 250 µA; VDS = VGS; Tj = 25 °C | 6 |
| Drain leakage current | IDSS |  |  | 1 | µA | VDS = 60 V; VGS = 0 V; Tj = 25 °C | 6 |
| Drain leakage current | IDSS |  |  | 10 | µA | VDS = 60 V; VGS = 0 V; Tj = 150 °C | 6 |
| Gate leakage current | IGSS |  |  | 10 | µA | VGS = 20 V; VDS = 0 V; Tj = 25 °C | 6 |
| Gate leakage current | IGSS |  |  | 1 | µA | VGS = 10 V; VDS = 0 V; Tj = 25 °C | 6 |
| Drain-source on-state resistance | RDSon |  | 1 | 1.6 | Ω | VGS = 10 V; ID = 350 mA; Tj = 25 °C | 6 |
| Drain-source on-state resistance | RDSon |  | 2 | 3.2 | Ω | VGS = 10 V; ID = 350 mA; Tj = 150 °C | 6 |
| Drain-source on-state resistance | RDSon |  | 1.1 | 2.2 | Ω | VGS = 4.5 V; ID = 200 mA; Tj = 25 °C | 6 |
| Drain-source on-state resistance | RDSon |  | 1.4 | 6.5 | Ω | VGS = 2.5 V; ID = 10 mA; Tj = 25 °C | 6 |
| Total gate charge | QG(tot) |  | 0.6 | 0.7 | nC | VDS = 30 V; ID = 300 mA; VGS = 4.5 V; Tj = 25 °C | 6 |
| Input capacitance | Ciss |  | 42 | 56 | pF | VDS = 10 V; f = 1 MHz; VGS = 0 V; Tj = 25 °C | 6 |
| Turn-on delay time | td(on) |  | 5 | 10 | ns | VDS = 40 V; RL = 250 Ω; VGS = 10 V; RG(ext) = 6 Ω; Tj = 25 °C | 6 |
| Turn-off delay time | td(off) |  | 38 | 76 | ns |  | 6 |
| Source-drain voltage | VSD | 0.47 | 0.8 | 1.2 | V | IS = 300 mA; VGS = 0 V; Tj = 25 °C | 6 |

## CAD (KiCad official)

- Symbol: `BSS138BK`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `bss138bk-etched.step` / `bss138bk-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bss138bk.step` / `bss138bk.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Nexperia datasheet](https://assets.nexperia.com/documents/data-sheet/BSS138BK.pdf) (16 pp, sha256 `7ee99c2ff94d07a9`, retrieved 2026-09-23, tier: manufacturer)
- **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/bss138bk-datasheet.pdf)