MMBZ5237BQ-7-F

Diodes Incorporated · Zener Diodes · SOT-23

MMBZ5237BQ-7-F from Diodes Incorporated, 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	Zener diode anode, connected to the diode in the device schematic (bottom-left terminal, top view).
2	NC	unconnected	No internal connection; the schematic shows this terminal (bottom-right, top view) not connected to the diode.
3	K	passive	Zener diode cathode, connected to the diode in the device schematic (top terminal, top view); the MMBZ5237B has a nominal VZ of 8.2V at IZT = 20mA.

Key specifications

Parameter	Value
Manufacturer	Diodes Incorporated
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	VZ	7.79	8.2	8.61	V	@ IZT = 20 mA; nominal 8.2 V (MMBZ5237B base part)	3
Maximum Zener impedance	ZZT			8	Ω	@ IZT = 20 mA, f = 1kHz	3
Maximum Zener impedance (knee)	ZZK			500	Ω	@ IZK = 0.25 mA	3
Maximum reverse leakage current	IR			3	µA	@ VR = 6.5 V	3
Forward voltage	VF			0.9	V	@ IF = 10mA	2
Power dissipation	PD			350	mW	Mounted on FR4 PC board with recommended pad layout (Note 6)	2
Thermal resistance, junction to ambient air	RθJA			357	°C/W	Mounted on FR4 PC board with recommended pad layout (Note 6)	2
Operating and storage temperature range	TJ, TSTG	-65		150	°C		2

Materials and finish

As the datasheet states them (page.json metadata.appearance; the 3D model's colours follow it).

Part	Material	Colour / plating	Datasheet says	Page
contacts		tin	 Terminal Connections: See Diagram  Terminals: Matte Tin Finish Annealed over Alloy 42 Leadframe	1

CAD (KiCad official)

Symbol: MMBZ5237BQ-7-F
Footprint: Package_TO_SOT_SMD:SOT-23
3D model: SOT-23 (KiCad packages3D, STEP)
3D model files: mmbz5237bq-7-f-etched.step / mmbz5237bq-7-f-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); mmbz5237bq-7-f.step / mmbz5237bq-7-f.glb are the bare package body.

Provenance

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

Datasheet: Diodes Incorporated datasheet (7 pp, sha256 be3510eb4019f5d5, 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

# MMBZ5237BQ-7-F

**Diodes Incorporated** · Zener Diodes · SOT-23

MMBZ5237BQ-7-F from Diodes Incorporated, 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 | Zener diode anode, connected to the diode in the device schematic (bottom-left terminal, top view). |
| 2 | NC | unconnected | No internal connection; the schematic shows this terminal (bottom-right, top view) not connected to the diode. |
| 3 | K | passive | Zener diode cathode, connected to the diode in the device schematic (top terminal, top view); the MMBZ5237B has a nominal VZ of 8.2V at IZT = 20mA. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Diodes Incorporated |
| 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 | VZ | 7.79 | 8.2 | 8.61 | V | @ IZT = 20 mA; nominal 8.2 V (MMBZ5237B base part) | 3 |
| Maximum Zener impedance | ZZT |  |  | 8 | Ω | @ IZT = 20 mA, f = 1kHz | 3 |
| Maximum Zener impedance (knee) | ZZK |  |  | 500 | Ω | @ IZK = 0.25 mA | 3 |
| Maximum reverse leakage current | IR |  |  | 3 | µA | @ VR = 6.5 V | 3 |
| Forward voltage | VF |  |  | 0.9 | V | @ IF = 10mA | 2 |
| Power dissipation | PD |  |  | 350 | mW | Mounted on FR4 PC board with recommended pad layout (Note 6) | 2 |
| Thermal resistance, junction to ambient air | RθJA |  |  | 357 | °C/W | Mounted on FR4 PC board with recommended pad layout (Note 6) | 2 |
| Operating and storage temperature range | TJ, TSTG | -65 |  | 150 | °C |  | 2 |

## Materials and finish

As the datasheet states them (page.json `metadata.appearance`; the 3D model's colours follow it).

| Part | Material | Colour / plating | Datasheet says | Page |
|---|---|---|---|---|
| contacts |  | tin |  Terminal Connections: See Diagram  Terminals: Matte Tin Finish Annealed over Alloy 42 Leadframe | 1 |

## CAD (KiCad official)

- Symbol: `MMBZ5237BQ-7-F`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `mmbz5237bq-7-f-etched.step` / `mmbz5237bq-7-f-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mmbz5237bq-7-f.step` / `mmbz5237bq-7-f.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Diodes Incorporated datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8560094038424133632) (7 pp, sha256 `be3510eb4019f5d5`, 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/mmbz5237bq-7-f-datasheet.pdf)