# RU40120S

**Shenzhen ruichips Semicon** · MOSFETs · TO-263

RU40120S from Shenzhen ruichips Semicon, in a TO-263. 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; controls the channel, with absolute maximum VGS of ±20 V and a threshold VGS(th) of 2 V min to 4 V max at IDS=250µA. |
| 2 | D | passive | Drain, connected to the exposed tab; VDSS is 40 V and continuous drain current is 120 A at TC=25°C (package limit 75A per note). |
| 3 | S | passive | Source; the diode continuous forward current IS is 120 A at TC=25°C. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Shenzhen ruichips Semicon |
| Package | TO-263 |
| 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 |  |  | 40 | V |  | 1 |
| Gate-Source Voltage | VGSS | -20 |  | 20 | V |  | 1 |
| Maximum Junction Temperature | TJ |  |  | 175 | °C |  | 1 |
| Storage Temperature Range | TSTG | -55 |  | 175 | °C |  | 1 |
| Continuous Drain Current | ID |  |  | 120 | A | VGS=10V, TC=25°C | 1 |
| Continuous Drain Current | ID |  |  | 103 | A | VGS=10V, TC=100°C | 1 |
| Diode Continuous Forward Current | IS |  |  | 120 | A | TC=25°C | 1 |
| 300μs Pulse Drain Current Tested | IDP |  |  | 480 | A | TC=25°C, pulse width limited by safe operating area | 1 |
| Maximum Power Dissipation | PD |  |  | 150 | W | TC=25°C, mounted on large heat sink | 1 |
| Maximum Power Dissipation | PD |  |  | 75 | W | TC=100°C, mounted on large heat sink | 1 |
| Avalanche Energy, Single Pulsed | EAS |  |  | 400 | mJ | Single pulsed; IAS=40A, VDD=32V, RG=50Ω, starting TJ=25°C | 1 |
| Thermal Resistance-Junction to Case | RθJC |  |  | 1 | °C/W |  | 1 |
| Thermal Resistance-Junction to Ambient | RθJA |  |  | 62.5 | °C/W |  | 1 |
| Drain-Source Breakdown Voltage | BVDSS | 40 |  |  | V | VGS=0V, IDS=250µA | 2 |
| Gate Threshold Voltage | VGS(th) | 2 |  | 4 | V | VDS=VGS, IDS=250µA | 2 |
| Gate Leakage Current | IGSS | -100 |  | 100 | nA | VGS=±20V, VDS=0V | 2 |
| Zero Gate Voltage Drain Current | IDSS |  |  | 1 | µA | VDS=40V, VGS=0V | 2 |
| Zero Gate Voltage Drain Current at TJ=125°C | IDSS |  |  | 30 | µA | TJ=125°C, VDS=40V, VGS=0V | 2 |
| Drain-Source On-state Resistance | RDS(ON) |  | 3.5 | 4.5 | mΩ | VGS=10V, IDS=60A; pulse test, pulse width ≤300µs, duty cycle ≤2% | 2 |

## CAD (KiCad official)

- Symbol: `RU40120S`
- Footprint: `Package_TO_SOT_SMD:TO-263-2`
- 3D model: TO-263 (KiCad packages3D, STEP)
- 3D model files: `ru40120s-etched.step` / `ru40120s-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ru40120s.step` / `ru40120s.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Shenzhen ruichips Semicon datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8586206746860277760) (8 pp, sha256 `05296866dffcd87e`, retrieved 2026-10-21, 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/ru40120s-datasheet.pdf)