# MMBZ5229B

**Slkor SLKORMICRO Elec** · Zener Diodes · SOT-23

MMBZ5229B from Slkor SLKORMICRO Elec, in a SOT-23. 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 | A | passive | Anode of the zener diode, shown as pin 1 in the connection diagram (forward voltage 0.9 V max at IF=10mA). |
| 2 | NC | unconnected | No connection, marked 2 NC in the connection diagram. |
| 3 | K | passive | Cathode of the zener diode, shown as pin 3 in the connection diagram (MMBZ5229B zener voltage 4.09 V min to 4.52 V max, 4.3 V nominal, at IZT=20mA). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Slkor SLKORMICRO Elec |
| Package | SOT-23 |
| Category | Diodes |
| 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 |
|---|---|---|---|---|---|---|---|
| Zener voltage (nominal 4.3 V, test current IZT = 20 mA) | VZ | 4.09 | 4.3 | 4.52 | V | IZT = 20 mA | 2 |
| Maximum zener impedance | ZZT |  |  | 22 | Ω | @ IZT = 20 mA | 2 |
| Maximum zener impedance (knee) | ZZK |  |  | 2000 | Ω | @ IZK = 0.25 mA | 2 |
| Maximum reverse leakage current | IR |  |  | 5 | μA | VR = 1.0 V | 2 |
| Forward voltage | VF |  |  | 0.9 | V | IF = 10 mA | 1 |
| Power dissipation | Pd |  |  | 350 | mW | Note 1: device terminals kept at ambient temperature | 1 |
| Thermal resistance, junction to ambient air | RθJA |  |  | 357 | ℃/W | Junction to ambient air | 1 |
| Operating and storage temperature range | Tj, Tstg | -65 |  | 150 | ℃ |  | 1 |

## CAD (KiCad official)

- Symbol: `MMBZ5229B`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `mmbz5229b-etched.step` / `mmbz5229b-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mmbz5229b.step` / `mmbz5229b.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Slkor SLKORMICRO Elec datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8756692812098756608) (4 pp, sha256 `8096af577e1c32df`, retrieved 2026-10-18, 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/mmbz5229b-datasheet.pdf)