# BAS21J

**Nexperia** · Global Sourcing Parts · SOD-323F

BAS21J from Nexperia, in a SOD-323F. 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 | cathode | passive | Cathode terminal, indicated by the marking bar; the cathode tab soldering point is the reference for the junction-to-solder-point thermal resistance Rth(j-sp) of 55 K/W. |
| 2 | anode | passive | Anode terminal of the single high-speed switching diode; the datasheet gives no pin-specific limit, and the limiting values (VR 300 V, IF 250 mA) apply to the device. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Nexperia |
| Package | SOD-323F |
| Category | Global Sourcing Parts |
| Pins | 2 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| repetitive peak reverse voltage | VRRM |  |  | 300 | V |  | 3 |
| reverse voltage | VR |  |  | 300 | V |  | 3 |
| forward current | IF |  |  | 250 | mA | [1] Pulse test: tp ≤ 300 µs; δ≤ 0.02 | 3 |
| repetitive peak forward current | IFRM |  |  | 1 | A | tp ≤ 0.5 ms; δ≤ 0.25 | 3 |
| non-repetitive peak forward current | IFSM |  |  | 3 | A | square wave; tp = 100 µs | 3 |
| non-repetitive peak forward current | IFSM |  |  | 2.3 | A | square wave; tp = 1 ms | 3 |
| non-repetitive peak forward current | IFSM |  |  | 1.7 | A | square wave; tp = 10 ms | 3 |
| total power dissipation | Ptot |  |  | 550 | mW | Tamb ≤ 25 °C | 3 |
| junction temperature | Tj |  |  | 150 | °C |  | 3 |
| ambient temperature | Tamb | -65 |  | 150 | °C |  | 3 |
| storage temperature | Tstg | -65 |  | 150 | °C |  | 3 |
| thermal resistance from junction to ambient | Rth(j-a) |  |  | 230 | K/W | in free air | 3 |
| thermal resistance from junction to solder point | Rth(j-sp) |  |  | 55 | K/W |  | 3 |
| forward voltage | VF |  |  | 1.1 | V | IF = 100 mA | 4 |
| reverse current | IR |  |  | 150 | nA | VR = 250 V | 4 |
| reverse current | IR |  |  | 50 | µA | VR = 250 V; Tj = 150 °C | 4 |
| diode capacitance | Cd |  |  | 2 | pF | VR = 0 V; f = 1 MHz | 4 |
| reverse recovery time | trr |  |  | 50 | ns | [2] When switched from IF = 30 mA to IR = 30 mA; RL = 100 Ω; measured at IR = 3 mA | 4 |

## CAD (KiCad official)

- Symbol: `BAS21J`
- Footprint: `Diode_SMD:D_SOD-323F`
- 3D model: SOD-323F (KiCad packages3D, STEP)
- 3D model files: `bas21j-etched.step` / `bas21j-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bas21j.step` / `bas21j.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Nexperia datasheet](https://assets.nexperia.com/documents/data-sheet/BAS21J.pdf) (10 pp, sha256 `7aad49d2c3d1d9ef`, retrieved 2026-10-26, tier: manufacturer)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `off` (skipped (clean text read)), 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/bas21j-datasheet.pdf)