# KY3400

**KY** · MOSFETs · SOT-23

KY3400 from KY, 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 | GATE | input | Gate terminal of the 30 V N-channel MOSFET, rated for gate-source voltage VGSS of ±12 V. |
| 2 | SOURCE | passive | Source terminal, the reference for the ±12 V gate-source rating and the 30 V drain-source rating (VDSS). |
| 3 | DRAIN | passive | Drain terminal, rated for drain-source voltage VDSS of 30 V and continuous drain current ID of 5.8 A (pulsed IDM 30 A). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | KY |
| 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 |  |  | 30 | V |  | 1 |
| Gate-Source Voltage | VGSS | -12 |  | 12 | V |  | 1 |
| Continuous Drain Current | ID |  |  | 5.8 | A |  | 1 |
| Pulsed Drain Current | IDM |  |  | 30 | A | note1: Pulse Width < 300µs, Duty Cycle ≤2% | 1 |
| Power Dissipation | PD |  |  | 0.35 | W |  | 1 |
| Thermal Resistance, Junction to Ambient | RθJA |  |  | 357 | ℃/W |  | 1 |
| Operating and Storage Temperature Range | TSTG | -55 |  | 150 | ℃ |  | 1 |
| Operating and Storage Temperature Range (junction) | TJ |  |  | 150 | ℃ |  | 1 |
| Drain-Source Breakdown Voltage | V(BR)DSS | 30 | 31.5 |  | V | VGS = 0V, ID = 250μA | 2 |
| Zero Gate Voltage Drain Current | IDSS |  |  | 1 | μA | VDS = 30V, VGS = 0V, TJ = 25℃ | 2 |
| Gate to Body Leakage Current | IGSS | -100 |  | 100 | nA | VGS = ±12V, VDS = 0V | 2 |
| Gate Threshold Voltage | VGS(th) | 0.7 | 1 | 1.4 | V | VDS = VGS, ID = 250μA | 2 |
| Static Drain-Source On-Resistance | RDS(on) |  | 21 | 33 | mΩ | VGS = 10V, ID = 5A | 2 |
| Static Drain-Source On-Resistance | RDS(on) |  | 25 | 39 | mΩ | VGS = 4.5V, ID = 4A | 2 |
| Static Drain-Source On-Resistance | RDS(on) |  | 36 | 60 | mΩ | VGS = 2.5V, ID = 3A | 2 |
| Drain to Source Diode Forward Voltage | VSD |  | 0.8 | 1 | V | VGS = 0V, ISD = 1A, TJ = 25℃ | 2 |
| Input Capacitance | Ciss |  |  | 1155 | pF | VDS = 15V, VGS = 0V, f = 1.0MHz | 2 |
| Turn-On Delay Time | td(on) |  |  | 5 | ns | VGS = 10V, VDS = 15V, RL = 2.7Ω, RGEN = 3Ω | 2 |
| Turn-On Rise Time | tr |  |  | 7 | ns | VGS = 10V, VDS = 15V, RL = 2.7Ω, RGEN = 3Ω | 2 |
| Turn-Off Delay Time | td(off) |  |  | 40 | ns | VGS = 10V, VDS = 15V, RL = 2.7Ω, RGEN = 3Ω | 2 |
| Turn-Off Fall Time | tf |  |  | 6 | ns | VGS = 10V, VDS = 15V, RL = 2.7Ω, RGEN = 3Ω | 2 |

## CAD (KiCad official)

- Symbol: `KY3400`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `ky3400-etched.step` / `ky3400-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ky3400.step` / `ky3400.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [KY datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590233248967262208) (5 pp, sha256 `5d9b0374c7af0a9d`, retrieved 2026-10-18, 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/ky3400-datasheet.pdf)