# SMB3Z190A

**XCH(旭昌辉)** · IC · SMB

SMB3Z190A from XCH(旭昌辉), in a SMB. 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, marked by the color band on the DO-214AA body; it goes positive of the anode in Zener (reverse) operation, with VZ 190 V nominal (180.5 to 199.5 V) at IZT 4.0 mA. |
| 2 | A | passive | Anode, the end opposite the color band; forward voltage is at most 1.2 V at 200 mA. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | XCH(旭昌辉) |
| Package | SMB |
| Category |  |
| 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 |
|---|---|---|---|---|---|---|---|
| Zener voltage (nominal, min, max) | VZ | 180.5 | 190 | 199.5 | V |  | 3 |
| Maximum Zener impedance | ZZT |  |  | 800 | Ω | @IZT 4.0 mA | 3 |
| Maximum Zener impedance (knee) | ZZK |  |  | 8000 | Ω | @IZK 0.25 mA | 3 |
| Maximum reverse leakage current | IR |  |  | 0.5 | uA | @VR 144.8 V | 3 |
| Maximum DC Zener current | IZM |  |  | 14 | mA |  | 3 |
| Maximum forward voltage | VF |  |  | 1.2 | V | IF=200mA | 1 |
| DC power dissipation | PD |  |  | 3 | W | TL = 75 °C (note 1) | 1 |
| Storage temperature range | TSTG | -55 |  | 150 | ℃ |  | 1 |
| Junction temperature range | TJ | -55 |  | 150 | ℃ |  | 1 |

## CAD (KiCad official)

- Symbol: `SMB3Z190A`
- Footprint: `Diode_SMD:D_SMB`
- 3D model: SMB (KiCad packages3D, STEP)
- 3D model files: `smb3z190a-etched.step` / `smb3z190a-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `smb3z190a.step` / `smb3z190a.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [XCH(旭昌辉) datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8603109744194437120) (3 pp, sha256 `f7084c044e53fbe6`, retrieved 2026-10-17, 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/smb3z190a-datasheet.pdf)