# JSM3420

**JSMSEMI** · MOSFETs · SOT-23

JSM3420 from JSMSEMI, 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 N-channel MOSFET; the datasheet limits gate-source voltage VGS to ±12V. |
| 2 | SOURCE | passive | Source terminal of the N-channel MOSFET; the datasheet rates the continuous source-drain diode current IS at 1.25A. |
| 3 | DRAIN | passive | Drain terminal of the N-channel MOSFET; the datasheet rates drain-source voltage VDS at 20V and continuous drain current ID at 6.0A. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | JSMSEMI |
| 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 |  |  | 20 | V | Ta=25℃ unless otherwise noted | 1 |
| Gate-Source Voltage | VGS | -12 |  | 12 | V | Printed as ±12; Ta=25℃ unless otherwise noted | 1 |
| Continuous Drain Current | ID |  |  | 6 | A | Ta=25℃ unless otherwise noted | 1 |
| Pulsed Drain Current | IDM |  |  | 20 | A | Pulse Width ≤300μs, Duty cycle ≤2% | 1 |
| Continuous Source-Drain Diode Current | IS |  |  | 1.25 | A | Ta=25℃ unless otherwise noted | 1 |
| Maximum Power Dissipation | PD |  |  | 1.25 | W | Ta=25℃ unless otherwise noted | 1 |
| Thermal Resistance from Junction to Ambient | RθJA |  |  | 100 | ℃/W | t ≤10s | 1 |
| Junction Temperature | TJ |  |  | 150 | ℃ |  | 1 |
| Storage Temperature | Tstg | -55 |  | 150 | ℃ |  | 1 |
| Drain-source breakdown voltage | V(BR)DSS | 20 |  |  | V | VGS = 0V, ID = 250µA | 2 |
| Gate-source threshold voltage | VGS(th) | 0.5 | 0.8 | 1 | V | VDS = VGS, ID = 250µA | 2 |
| Gate-source leakage | IGSS | -100 |  | 100 | nA | VDS = 0V, VGS = ±12V | 2 |
| Zero gate voltage drain current | IDSS |  |  | 100 | A | VDS = 16V, VGS = 0V | 2 |
| Drain-source on-state resistance | RDS(on) |  | 0.019 | 0.027 | Ω | VGS = 4.5V, ID = 5A | 2 |
| Drain-source on-state resistance | RDS(on) |  | 0.023 | 0.035 | Ω | VGS = 2.5V, ID = 4A | 2 |
| Drain-source on-state resistance | RDS(on) |  | 0.016 | 0.024 | Ω | VGS = 10V, ID = 6A | 2 |
| Forward transconductance | gfs | 25 |  |  | S | VDS = 5V, ID = 6A | 2 |
| Body diode voltage | VSD |  | 0.7 | 1 | V | IS = 1.0A | 2 |

## CAD (KiCad official)

- Symbol: `JSM3420`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `jsm3420-etched.step` / `jsm3420-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `jsm3420.step` / `jsm3420.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [JSMSEMI datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588917247082942464) (6 pp, sha256 `464f37bcc5ebd4ff`, retrieved 2026-10-09, 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/jsm3420-datasheet.pdf)