component
MMBZ5259B
Public Made by Adomby adom
Changjing Zener Diodes, SOT-23. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
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MMBZ5259B
Changjing · Zener Diodes · SOT-23
MMBZ5259B from Changjing, 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 anode, shown in the page 1 symbol as the diode input side; the datasheet gives forward voltage VF 0.9 V at IF = 10 mA. |
| 2 | NC | unconnected | No connection; shown in the page 1 symbol as an open pin not tied to the diode. |
| 3 | K | passive | Zener cathode, shown in the page 1 symbol on the bar side of the diode; the MMBZ5259B has a nominal VZ of 39 V (37.05 V to 40.95 V) at IZT = 3.2 mA, with power dissipation of 300 mW. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| 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 39 V, min/max) | VZ | 37.05 | 39 | 40.95 | V | IZT = 3.2 mA; short duration test pulse | 2 |
| Maximum Zener impedance | ZZT | 80 | Ω | @ IZT = 3.2 mA | 2 | ||
| Maximum Zener impedance (knee) | ZZK | 800 | Ω | @ IZK = 0.25 mA | 2 | ||
| Maximum reverse leakage current | IR | 0.1 | µA | @ VR = 30 V | 2 | ||
| Operation junction and storage temperature range | TJ,TSTG | -55 | 150 | ℃ | 1 | ||
| Power dissipation | PD | 300 | mW | 1 | |||
| Forward voltage | VF | 0.9 | V | @ IF = 10 mA | 1 | ||
| Thermal resistance, junction to ambient | R JA | 417 | ℃/W | 1 |
CAD (KiCad official)
- Symbol:
MMBZ5259B - Footprint:
Package_TO_SOT_SMD:SOT-23 - 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files:
mmbz5259b-etched.step/mmbz5259b-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);mmbz5259b.step/mmbz5259b.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: Changjing datasheet (5 pp, sha256
eab0dbad2cbe9e7d, retrieved 2026-10-19, tier: lcsc) - Extractor: parts-factory
2.0.0/extract_pins 0.3, primaryclaude-sonnet-5-5(text+vision), consensusclaude-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).
# MMBZ5259B
**Changjing** · Zener Diodes · SOT-23
MMBZ5259B from Changjing, 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 anode, shown in the page 1 symbol as the diode input side; the datasheet gives forward voltage VF 0.9 V at IF = 10 mA. |
| 2 | NC | unconnected | No connection; shown in the page 1 symbol as an open pin not tied to the diode. |
| 3 | K | passive | Zener cathode, shown in the page 1 symbol on the bar side of the diode; the MMBZ5259B has a nominal VZ of 39 V (37.05 V to 40.95 V) at IZT = 3.2 mA, with power dissipation of 300 mW. |
## Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| 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 39 V, min/max) | VZ | 37.05 | 39 | 40.95 | V | IZT = 3.2 mA; short duration test pulse | 2 |
| Maximum Zener impedance | ZZT | | | 80 | Ω | @ IZT = 3.2 mA | 2 |
| Maximum Zener impedance (knee) | ZZK | | | 800 | Ω | @ IZK = 0.25 mA | 2 |
| Maximum reverse leakage current | IR | | | 0.1 | µA | @ VR = 30 V | 2 |
| Operation junction and storage temperature range | TJ,TSTG | -55 | | 150 | ℃ | | 1 |
| Power dissipation | PD | | | 300 | mW | | 1 |
| Forward voltage | VF | | | 0.9 | V | @ IF = 10 mA | 1 |
| Thermal resistance, junction to ambient | R JA | | | 417 | ℃/W | | 1 |
## CAD (KiCad official)
- Symbol: `MMBZ5259B`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `mmbz5259b-etched.step` / `mmbz5259b-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mmbz5259b.step` / `mmbz5259b.glb` are the bare package body.
## Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- **Datasheet:** [Changjing datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590456510544445440) (5 pp, sha256 `eab0dbad2cbe9e7d`, retrieved 2026-10-19, 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/mmbz5259b-datasheet.pdf)