# WR0205

**WEIDA** · Thyristors (SCR)/Modules · SOT-223

WR0205 from WEIDA, in a SOT-223. 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 of the SCR (K(1) in the device symbol); the SCR is rated for IT(RMS) 2 A on-state current. |
| 2 | A | passive | Anode of the SCR (A(2) in the device symbol); the SCR blocks VDRM/VRRM of 600/800 V. |
| 3 | G | input | Gate of the SCR (G(3) in the device symbol); trigger current IGT is 40 µA typical and 200 µA max at VD=12 V, RL=33 Ω. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | WEIDA |
| Package | SOT-223 |
| 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 |
|---|---|---|---|---|---|---|---|
| Gate trigger current | IGT |  | 40 | 200 | µA | VD=12V, RL=33Ω | 2 |
| Gate trigger voltage | VGT |  | 0.5 | 1.5 | V | VD=12V, RL=33Ω | 2 |
| Gate non-trigger voltage | VGD | 0.2 |  |  | V | VD=VDRM Tj=110℃ RL=3.3kΩ | 2 |
| Holding current | IH |  |  | 2 | mA | IT=50mA | 2 |
| Latching current | IL |  |  | 3 | mA | IG=1.2IGT | 2 |
| Critical rate of rise of off-state voltage | dV/dt | 10 |  |  | V/µs | VD=0.66×VDRM Tj=110℃ G 极开路 RGK=1KΩ | 2 |
| On-state voltage | VTM |  |  | 1.5 | V | ITM=4A tp=380μs Tj=25℃ | 2 |
| Repetitive peak off-state and reverse current | IDRM/IRRM |  |  | 5 | µA | VDRM= VRRM RGK=1KΩ Tj=25℃ | 2 |
| Repetitive peak off-state and reverse current | IDRM/IRRM |  |  | 100 | µA | VDRM= VRRM RGK=1KΩ Tj=110℃ | 2 |
| Storage junction temperature range | Tstg | -40 |  | 150 | ℃ |  | 1 |
| Operating junction temperature range | Tj | -40 |  | 110 | ℃ |  | 1 |
| RMS on-state current | IT(RMS) |  |  | 2 | A |  | 1 |
| Non repetitive surge peak on-state current | ITSM |  |  | 20 | A | full cycle, F=50Hz | 1 |
| I2t value for fusing | I2t |  |  | 2 | A2s | tp=10ms | 1 |
| Critical rate of rise of on-state current | dI/dt |  |  | 50 | A/µs | IG=2×IGT | 2 |
| Peak gate current | IGM |  |  | 0.2 | A |  | 2 |
| Average gate power dissipation | PG(AV) |  |  | 0.1 | W |  | 2 |
| Peak gate power | PGM |  |  | 0.5 | W |  | 2 |
| Thermal resistance junction to case (AC), SOT-223 | Rth(j-c) |  |  | 20 | ℃/W | junction to case(AC), SOT-223-3L | 3 |

## CAD (KiCad official)

- Symbol: `WR0205`
- Footprint: `Package_TO_SOT_SMD:SOT-223-3_TabPin2`
- 3D model: SOT-223 (KiCad packages3D, STEP)
- 3D model files: `wr0205-etched.step` / `wr0205-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `wr0205.step` / `wr0205.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [WEIDA datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588944613826969600) (8 pp, sha256 `211f0ac51b9f64d2`, retrieved 2026-10-09, 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/wr0205-datasheet.pdf)