Alternatives to onsemi MMBZ5242B
onsemi MMBZ5242B and its qualified second sources, compared on form/fit/function, stock, lifecycle and price — the same checks Parter runs inside a BOM.
 MMBZ5242Bonsemi |  MMBZ5242BLT1Gonsemi |  MMBZ5242B-7-FDiodes Incorporated | +3more | |
|---|---|---|---|---|
| FFF Compatibility | Identical SOT-23-3 package dimensions and pin assignments (Pin 1: Anode, Pin 2: NC, Pin 3: Cathode).Direct physical footprint and package outline match.Functionally equivalent except for a lower maximum power rating specification (225 mW vs 350 mW). | Identical SOT-23 package outline and pinouts (Pin 1: Anode, Pin 2: NC, Pin 3: Cathode).Exact physical SOT-23 package shape, dimensions, and mounting style.Meets or exceeds all original electrical specifications, including the 350 mW power rating. | ||
 AI Summary | MMBZ5242B by onsemi: Zener Diode 12 V 350 mW ±5% Surface Mount SOT-23-3. | This is the direct modern successor and active sibling from onsemi, offering the same 12V Zener voltage and pinout. While its maximum power rating is specified at 225 mW compared to the original 350 mW specification, this is largely a result of standardized modern datasheet testing on minimal copper land pads. For most standard signal-level circuits, it operates as a direct drop-in replacement.
| This is an active, highly reliable second-source replacement from Diodes Incorporated. It perfectly matches the original 350 mW power dissipation limit and electrical tolerances, offering a direct drop-in solution without requiring any board modifications. It features the standard '-7-F' packing code denoting a lead-free, environmentally green device on a 7-inch reel.
| |
| Lifecycle Status | Obsolete | Active | Active | |
| Market Availability | Non-stock | In stock | In stock | |
| REACH | REACH | REACH | REACH | |
| RoHS | RoHS | RoHS | RoHS | |
| Description | Zener Diode 12 V 350 mW ±5% Surface Mount SOT-23-3 | Zener Diode 12 V 225 mW ±5% Surface Mount SOT-23-3 (TO-236) | Zener Diode 12 V 350 mW ±5% Surface Mount SOT-23-3 | |
| Manufacturer | onsemi | onsemi | Diodes Incorporated | |
| Type | Diodes | Diodes | Diodes | |
| Datasheet | Open | Open | Open | |
| Lead Time | 31 weeks | 52 weeks | 52 weeks | |
| Country of Origin | JP | - | - | |
| Export Control Class Number | EAR99 | EAR99 | EAR99 | |
| HTSUS Code | 8541.10.0050 | - | - | |
| Moisture Sensitivity Level | 1 (Unlimited) | - | - | |
| Tolerance | ±5% | - | - | |
| Power - Max | 350 mW | - | - | |
| Mounting Type | Surface Mount | - | - | |
| Package / Case | TO-236-3, SC-59, SOT-23-3 | - | - | |
| Impedance (Max) (Zzt) | 30 Ohms | - | - |
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Related parts
| Part | Market availability | Lifecycle | Alternatives available |
|---|---|---|---|
 MMBZ5242BLT1onsemi | Discontinued | Obsolete | 6Alternatives availableSee Alternatives |
 MMSZ5245Bonsemi | In stock | Obsolete | 5Alternatives availableSee Alternatives |
 MMBT2222Aonsemi | In stock | Obsolete | 4Alternatives availableSee Alternatives |
| SMBJ24ADiodes Incorporated | Discontinued | Obsolete | 7Alternatives availableSee Alternatives |
 DL5245BDiodes Incorporated | Non-stock | Obsolete | 5Alternatives availableSee Alternatives |
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Frequently asked questions
Yes. The onsemi MMBZ5242B 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 MMBZ5242B are the MMBZ5242BLT1G (onsemi) and the MMBZ5242B-7-F (Diodes Incorporated), out of 5 matched alternatives in total. Each is compared against the original on fit, form and function in the table above.
Partly. Some alternatives to the MMBZ5242B are full fit-, form- and function-compatible drop-ins, while others match on function but differ in package or a key parameter. Check the fit/form/function notes in the table and the datasheet for your application before swapping.
The MMBZ5242B (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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