# MMBZ5241BLT1G

**onsemi** · Zener Diodes · SOT-23

MMBZ5241BLT1G from onsemi, 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 | ANODE | passive | Zener diode anode, per CASE 318 STYLE 8 pin 1 ANODE; the 225 mW rated part is a Zener voltage regulator with Vz nominal 11 V for MMBZ5241BLT1G. |
| 2 | NC | unconnected | No connection, as listed for pin 2 in the STYLE 8 outline and the Electrical Characteristics pinout (1-Anode, 2-NC, 3-Cathode). |
| 3 | CATHODE | passive | Zener diode cathode, per CASE 318 STYLE 8 pin 3 CATHODE; the cathode is indicated by the polarity band on the package. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | onsemi |
| 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 |
|---|---|---|---|---|---|---|---|
| Reverse Zener Voltage (min) | VZ | 10.4 |  |  | V | @ IZT = 20 mA; pulse test, TA = 25°C (Note 3) | 3 |
| Reverse Zener Voltage (max) | VZ |  |  | 11.55 | V | @ IZT = 20 mA; pulse test, TA = 25°C (Note 3) | 3 |
| Maximum Zener Impedance | ZZT |  |  | 22 | Ω | @ IZT = 20 mA | 3 |
| Maximum Zener Impedance | ZZK |  |  | 600 | Ω | @ IZK = 0.25 mA | 3 |
| Reverse Leakage Current | IR |  |  | 2 | µA | @ VR = 8.4 V | 3 |
| Forward Voltage | VF |  |  | 0.9 | V | @ IF = 10 mA (note: VF = 0.9 V Max @ IF = 10 mA for all types) | 3 |
| Nominal Zener Voltage | VZ |  | 11 |  | V | @ IZT = 20 mA | 3 |
| Total Power Dissipation on FR-5 Board | PD |  |  | 225 | mW | TA = 25°C; FR-5 board (Note 1) | 1 |
| Power Derating above 25°C on FR-5 Board |  |  | 1.8 |  | mW/°C | derated above 25°C; FR-5 board (Note 1) | 1 |
| Total Power Dissipation on Alumina Substrate | PD |  |  | 300 | mW | TA = 25°C; alumina substrate (Note 2) | 1 |
| Power Derating above 25°C on Alumina Substrate |  |  | 2.4 |  | mW/°C | derated above 25°C; alumina substrate (Note 2) | 1 |
| Thermal Resistance, Junction-to-Ambient (FR-5 board) | RJA |  |  | 556 | °C/W | FR-5 board (Note 1) | 1 |
| Thermal Resistance, Junction-to-Ambient (alumina substrate) | RJA |  |  | 417 | °C/W | alumina substrate (Note 2) | 1 |
| Junction and Storage Temperature Range | TJ, Tstg | -65 |  | 150 | °C |  | 1 |

## CAD (KiCad official)

- Symbol: `MMBZ5241BLT1G`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `mmbz5241blt1g-etched.step` / `mmbz5241blt1g-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mmbz5241blt1g.step` / `mmbz5241blt1g.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [onsemi datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8589979986339143680) (7 pp, sha256 `f5bdb6eb025b64cd`, retrieved 2026-10-17, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-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/mmbz5241blt1g-datasheet.pdf)