# BTA41-1200B

**KY** · TRIACs · TO-3P-3

BTA41-1200B from KY, in a TO-3P-3. 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 | T1 | passive | Main terminal T1 of the triac, shown as T1(1) in the symbol; the TO-3P Insulated package is rated IT(RMS) 40A at Tc=110°C. |
| 2 | T2 | passive | Main terminal T2 of the triac, shown as T2(2) in the symbol; BTA41-1200B has VDRM/VRRM of 1200V. |
| 3 | G | input | Gate terminal, shown as G(3) in the symbol; gate trigger voltage VGT is ≤1.5V at VD=12V, RL=30Ω. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | KY |
| Package | TO-3P-3 |
| Category | Transistors |
| 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 |
|---|---|---|---|---|---|---|---|
| Repetitive Peak Off-State Voltage (VDRM/VRRM), BTA41-1200B | VDRM/VRRM |  |  | 1200 | V |  | 3 |
| R.M.S On-State Current | IT(RMS) |  |  | 40 | A | Tc=110°C | 3 |
| Surge On-State Current (first printed value of 400/420) | ITSM |  |  | 400 | A |  | 3 |
| Surge On-State Current (second printed value of 400/420) | ITSM |  |  | 420 | A |  | 3 |
| I2t for fusing | I²t |  |  | 520 | A²s | Tp=10ms | 3 |
| Average Gate Power Dissipation | PG(AV) |  |  | 1 | W | Tj=125°C | 3 |
| Peak Gate Current | IGM |  |  | 8 | A | Tj=125°C | 3 |
| Operating Junction Temperature | Tj | -40 |  | 125 | °C |  | 3 |
| Storage Temperature | TSTG | -40 |  | 150 | °C |  | 3 |
| Repetitive Peak Off-State Current | IDRM |  |  | 5 | uA | Tj=25°C | 3 |
| Repetitive Peak Off-State Current | IDRM |  |  | 5 | mA | Tc=125°C | 3 |
| Repetitive Peak Reverse Current | IRRM |  |  | 5 | uA | Tc=25°C | 3 |
| Repetitive Peak Reverse Current | IRRM |  |  | 5 | mA | Tc=125°C | 3 |
| Forward on voltage | VTM |  |  | 1.55 | V | IT=23A, tp=380us | 3 |
| Gate trigger voltage | VGT |  |  | 1.5 | V | VD=12V, RL=30Ω | 3 |
| Gate trigger current, quadrants I, II, III | IGT |  |  | 50 | mA | VD=12V, RL=30Ω, quadrants I, II, III | 3 |
| Gate trigger current, quadrant IV | IGT |  |  | 100 | mA | VD=12V, RL=30Ω, quadrant IV | 3 |
| Holding current | IH |  |  | 80 | mA | IT=0.2A | 3 |
| Critical rate of rise of commutation voltage | dv/dt | 1000 |  |  | V/us | TJ=125°C, VD=2/3VDRM, gate open circuit | 3 |

## CAD (KiCad official)

- Symbol: `BTA41-1200B`
- Footprint: `Package_TO_SOT_THT:TO-3P-3_Vertical`
- 3D model: TO-3P-3 (KiCad packages3D, STEP)
- 3D model files: `bta41-1200b-etched.step` / `bta41-1200b-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bta41-1200b.step` / `bta41-1200b.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [KY datasheet](docs/bta41-1200b-datasheet.pdf) (6 pp, sha256 `2ee660fe74201220`, retrieved 2026-11-05, 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/bta41-1200b-datasheet.pdf)