# BSS138BKT116

**ROHM Semicon** · MOSFETs · SOT-23

BSS138BKT116 from ROHM Semicon, 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 | Source | passive | Source terminal of the N-channel MOSFET, shared with the body diode anode and the gate ESD protection diode. |
| 2 | Gate | input | Gate terminal with ESD protection diode (up to 2kV HBM), gate-source voltage limited to ±20V, 2.5V drive, threshold 0.8 to 2.0V. |
| 3 | Drain | passive | Drain terminal of the N-channel MOSFET, rated for 60V drain-source voltage and ±400mA continuous drain current. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | ROHM Semicon |
| 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 | VDSS |  |  | 60 | V |  | 1 |
| Continuous drain current | ID | -400 |  | 400 | mA |  | 1 |
| Pulsed drain current | IDP | -1.4 |  | 1.4 | A | Pw ≤ 10μs, Duty cycle ≤ 1% | 1 |
| Gate - Source voltage | VGSS | -20 |  | 20 | V |  | 1 |
| Power dissipation | PD |  |  | 350 | mW | Mounted on a ceramic board (30mm×30mm×0.8mm) | 1 |
| Power dissipation | PD |  |  | 200 | mW | Mounted on a FR4 board (20mm×12mm×0.8mm，Cu pad=0.8m㎡) | 1 |
| Junction temperature | Tj |  |  | 150 | ℃ |  | 1 |
| Operating junction and storage temperature range | Tstg | -55 |  | 150 | ℃ |  | 1 |
| Thermal resistance, junction - ambient | RthJA |  |  | 357 | ℃/W | Mounted on a ceramic board (30mm×30mm×0.8mm) | 2 |
| Thermal resistance, junction - ambient | RthJA |  |  | 625 | ℃/W | Mounted on a FR4 board (20mm×12mm×0.8mm，Cu pad=0.8m㎡) | 2 |
| Drain - Source breakdown voltage | V(BR)DSS | 60 |  |  | V | VGS = 0V, ID = 1mA | 2 |
| Zero gate voltage drain current | IDSS |  |  | 1 | μA | VDS = 60V, VGS = 0V | 2 |
| Gate - Source leakage current | IGSS | -10 |  | 10 | μA | VGS = ±20V, VDS = 0V | 2 |
| Gate threshold voltage | VGS(th) | 0.8 |  | 2 | V | VDS = VGS, ID = 10μA | 2 |
| Static drain - source on - state resistance | RDS(on) |  | 0.49 | 0.68 | Ω | VGS = 10V, ID = 400mA (pulsed) | 2 |
| Static drain - source on - state resistance | RDS(on) |  | 0.58 | 0.81 | Ω | VGS = 4.5V, ID = 400mA (pulsed) | 2 |
| Static drain - source on - state resistance | RDS(on) |  | 1 | 4 | Ω | VGS = 2.5V, ID = 10mA (pulsed) | 2 |
| Forward Transfer Admittance | /Yfs/ | 0.5 |  |  | S | VDS = 10V, ID = 400mA (pulsed) | 2 |
| Continuous forward current | IS |  |  | 0.29 | A | Ta = 25℃ | 3 |
| Pulse forward current | ISP |  |  | 1.4 | A | Pw ≤ 10μs, Duty cycle ≤ 1% | 3 |
| Forward voltage | VSD |  |  | 1.2 | V | VGS = 0V, IS = 290mA (pulsed) | 3 |

## CAD (KiCad official)

- Symbol: `BSS138BKT116`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `bss138bkt116-etched.step` / `bss138bkt116-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bss138bkt116.step` / `bss138bkt116.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [ROHM Semicon datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8603052025576386560) (14 pp, sha256 `82ddb408f61e77d7`, retrieved 2026-10-19, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (text+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/bss138bkt116-datasheet.pdf)