# US1AL

**Changjing** · Fast Recovery / High Efficiency Diodes · SOD-123FL

US1AL from Changjing, in a SOD-123FL. 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 | K | passive | Cathode: the banded/marked end per the datasheet; pad 1 of the KiCad diode footprint. |
| 2 | A | passive | Anode. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| Package | SOD-123FL |
| Category | Diodes |
| 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 |  |  | 50 | V |  | 1 |
| Maximum RMS Voltage | V RMS |  |  | 35 | V |  | 1 |
| Average Forward Current | IF(AV) |  |  | 1 | A | 60Hz half-sine wave, resistance load, Ta=90℃ | 1 |
| Peak Forward Voltage | VF |  |  | 1.3 | V | IF=1.0A | 1 |
| Peak Reverse Current | IRRM1 |  |  | 5 | µA | VRM=VRRM, Ta=25℃ | 1 |
| Peak Reverse Current | IRRM2 |  |  | 50 | µA | VRM=VRRM, Ta=125℃ | 1 |
| Operation Junction and Storage Temperature Range | TJ,TSTG | -55 |  | 150 | ℃ |  | 1 |

## Materials and finish

As the datasheet states them (page.json `metadata.appearance`; the 3D model's colours follow it).

| Part | Material | Colour / plating | Datasheet says | Page |
|---|---|---|---|---|
| contacts | copper |  | Thermal resistance from junction to ambient and from junction to lead mounted on P.C.B. with 0.2" x 0.2" (5.0 mm x 5.0 mm) copper | 1 |

## CAD (KiCad official)

- Symbol: `US1AL`
- Footprint: `Diode_SMD:D_SOD-123F`
- 3D model: SOD-123FL (KiCad packages3D, STEP)
- 3D model files: `us1al-etched.step` / `us1al-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `us1al.step` / `us1al.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Changjing datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590906445494247424) (4 pp, sha256 `12a271a3118f6926`, retrieved 2026-10-16, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins`, primary `cathode-band convention` (convention), consensus `off` (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/us1al-datasheet.pdf)