Alternatives to onsemi MMSZ5239B
onsemi MMSZ5239B and its qualified second sources, compared on form/fit/function, stock, lifecycle and price — the same checks Parter runs inside a BOM.
 MMSZ5239Bonsemi |  MMSZ5239BT1Gonsemi |  MMSZ5239B-7-FDiodes Incorporated | +4more | |
|---|---|---|---|---|
| FFF Compatibility | The device utilizes the identical SOD-123 footprint with Cathode on Pin 1 and Anode on Pin 2.The package style and dimensions are identical to the original SOD-123 specification.All electrical characteristics (9.1V Zener voltage, 500mW max power, and 10 Ohm impedance) perfectly match the original. | Utilizes the standard SOD-123 package with Cathode on Pin 1 and Anode on Pin 2.Matches the physical dimensions and lead form of the original component.Meets or exceeds all original parameters, including an extended operating temperature down to -65°C. | ||
 AI Summary | MMSZ5239B by onsemi: Zener Diode 9.1 V 500 mW ±5% Surface Mount SOD-123. | This is the direct active successor from the original manufacturer (onsemi). It shares identical form, fit, and functional characteristics, serving as a seamless drop-in replacement for the obsolete MMSZ5239B.
| This is a direct equivalent drop-in replacement manufactured by Diodes Incorporated. It is fully active, widely available, and matches the original electrical and physical profiles exactly.
| |
| Lifecycle Status | Obsolete | Active | Active | |
| Market Availability | In stock | In stock | In stock | |
| REACH | REACH | REACH | REACH | |
| RoHS | RoHS | RoHS | RoHS | |
| Description | Zener Diode 9.1 V 500 mW ±5% Surface Mount SOD-123 | Zener Diode 9.1 V 500 mW ±5% Surface Mount SOD-123 | Zener Diode 9.1 V 500 mW ±5% Surface Mount SOD-123 | |
| Manufacturer | onsemi | onsemi | Diodes Incorporated | |
| Type | Diodes | Diodes | Diodes | |
| Datasheet | Open | Open | Open | |
| Lead Time | 13 weeks | 44 weeks | 40 weeks | |
| Country of Origin | CN | - | - | |
| Export Control Class Number | EAR99 | EAR99 | EAR99 | |
| HTSUS Code | 8541.10.0050 | - | - | |
| Moisture Sensitivity Level | 1 (Unlimited) | - | - | |
| Tolerance | ±5% | - | - | |
| Power - Max | 500 mW | - | - | |
| Mounting Type | Surface Mount | - | - | |
| Package / Case | SOD-123 | - | - | |
| Impedance (Max) (Zzt) | 10 Ohms | - | - | |
| Operating Temperature | -55°C ~ 150°C | - | - | |
| Supplier Device Package | SOD-123 | - | - | |
| Voltage - Zener (Nom) (Vz) | 9.1 V | - | - |
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Related parts
| Part | Market availability | Lifecycle | Alternatives available |
|---|---|---|---|
 MMSZ5226Bonsemi | Discontinued | Obsolete | 5Alternatives availableSee Alternatives |
| MMSZ5242Bonsemi | Non-stock | Obsolete | 3Alternatives availableSee Alternatives |
| MMSZ5245Bonsemi | In stock | Obsolete | 5Alternatives availableSee Alternatives |
 MMSZ4697T1onsemi | Discontinued | Obsolete | 7Alternatives availableSee Alternatives |
| MMSD914onsemi | In stock | Obsolete | 8Alternatives availableSee Alternatives |
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Frequently asked questions
Yes. The onsemi MMSZ5239B is marked obsolete, so the manufacturer has discontinued it and any remaining supply is limited to distributor stock. The qualified second sources on this page are active parts you can design in today.
The closest qualified second sources for the onsemi MMSZ5239B are the MMSZ5239BT1G (onsemi) and the MMSZ5239B-7-F (Diodes Incorporated), out of 6 matched alternatives in total. Each is compared against the original on fit, form and function in the table above.
Not always. The alternatives to the MMSZ5239B are matched on function but can differ in package, pinout or a key parameter, so review the fit/form/function notes in the table and the datasheet before designing one in.
The MMSZ5239B (onsemi) is a part in the Diodes category. This page lists qualified, cross-referenced replacements for it with a side-by-side comparison.
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