# WSF7N40

**Winsok Semicon** · MOSFETs · TO-252

WSF7N40 from Winsok Semicon, in a TO-252. 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 | G | input | Gate; gate-source voltage is limited to ±30 V absolute maximum, with a typical threshold of 3.5 V (2.0 V min, 4.0 V max) at ID=250uA. |
| 2 | D | passive | Drain, also connected to the exposed tab; drain-source voltage is rated 400 V with 7 A continuous drain current at TC=25℃ and 28 A pulsed. |
| 3 | S | passive | Source; continuous body-diode source current is 7 A max and pulsed source current is 28 A max. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Winsok Semicon |
| Package | TO-252 |
| 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 |  |  | 400 | V |  | 1 |
| Gate-Source Voltage | VGS | -30 |  | 30 | V |  | 1 |
| Continuous Drain Current | ID@TC=25℃ |  |  | 7 | A | VGS @ 10V | 1 |
| Continuous Drain Current | ID@TC=100℃ |  |  | 4 | A | VGS @ 10V | 1 |
| Pulsed Drain Current | IDM |  |  | 28 | A |  | 1 |
| Single Pulse Avalanche Energy | EAS |  |  | 176 | mJ |  | 1 |
| Avalanche Current | IAR |  |  | 7 | A |  | 1 |
| Total Power Dissipation | PD@TC=25℃ |  |  | 33 | W |  | 1 |
| Storage Temperature Range | TSTG | -55 |  | 150 | ℃ |  | 1 |
| Operating Junction Temperature Range | TJ | -55 |  | 150 | ℃ |  | 1 |
| Thermal Resistance Junction-ambient | RθJA |  |  | 60 | ℃/W | Surface mounted on 1 inch² FR-4 board, 2OZ copper, t<10sec | 1 |
| Thermal Resistance Junction-Case | RθJC |  |  | 3.8 | ℃/W | Surface mounted on 1 inch² FR-4 board, 2OZ copper, t<10sec | 1 |
| Drain-Source Breakdown Voltage | BVDSS | 400 |  |  | V | VGS=0V, ID=250uA | 2 |
| Static Drain-Source On-Resistance | RDS(ON) |  | 0.8 | 1.1 | Ω | VGS=10V, ID=4A | 2 |
| Gate Threshold Voltage | VGS(th) | 2 | 3.5 | 4 | V | VGS=VDS, ID=250uA | 2 |
| Drain-Source Leakage Current | IDSS |  |  | 1 | uA | VDS=400V, VGS=0V, TJ=25℃ | 2 |
| Drain-Source Leakage Current | IDSS |  |  | 10 | uA | VDS=400V, VGS=0V, TJ=125℃ | 2 |
| Gate-Source Leakage Current | IGSS | -100 |  | 100 | nA | VGS=±30V, VDS=0V | 2 |
| Single Pulse Avalanche Energy | EAS | 90 |  |  | mJ | VDD=50V, L=0.1mH, IAS=4.5A | 2 |
| Continuous Source Current | IS |  |  | 7 | A | VG=VD=0V, Force Current | 2 |
| Pulsed Source Current | ISM |  |  | 28 | A |  | 2 |
| Diode Forward Voltage | VSD |  |  | 1.4 | V | VGS=0V, IS=7A, TJ=25℃ | 2 |

## CAD (KiCad official)

- Symbol: `WSF7N40`
- Footprint: `Package_TO_SOT_SMD:TO-252-2`
- 3D model: TO-252 (KiCad packages3D, STEP)
- 3D model files: `wsf7n40-etched.step` / `wsf7n40-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `wsf7n40.step` / `wsf7n40.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Winsok Semicon datasheet](docs/wsf7n40-datasheet.pdf) (5 pp, sha256 `1657071358a26743`, retrieved 2026-11-04, 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/wsf7n40-datasheet.pdf)