Alternatives to onsemi MMBT100A
onsemi MMBT100A and its qualified second sources, compared on form/fit/function, stock, lifecycle and price — the same checks Parter runs inside a BOM.
 MMBT100Aonsemi |  BC817-40LT1Gonsemi |  BCX19T116Rohm Semiconductor | +2more | |
|---|---|---|---|---|
| FFF Compatibility | SOT-23-3 footprint and pinout (1-Base, 2-Emitter, 3-Collector) are identical.Same standard SOT-23 package dimensions.Electrical specs closely match, with identical maximum ratings (45 V, 500 mA). | Identical SOT-23 pin configuration (1-Base, 2-Emitter, 3-Collector).Standard SOT-23 (SST3) package dimensions.Has a lower DC current gain (hFE) minimum of 100 compared to the original 300. | ||
 AI Summary | MMBT100A by onsemi: Bipolar (BJT) Transistor NPN 45 V 500 mA 250MHz 350 mW Surface Mount SOT-23-3. | This is the primary replacement option from onsemi. It retains the same physical SOT-23-3 package and pinout while matching the 45 V collector-emitter voltage and 500 mA collector current ratings. Its high gain classification (hFE of 250 minimum) serves as an excellent match for the original MMBT100A gain profile.
| This active part from Rohm matches the original maximum power dissipation of 350 mW and transition frequency of 250 MHz perfectly. However, the DC current gain minimum is lower, which may affect circuit behavior in gain-sensitive applications.
| |
| Lifecycle Status | Obsolete | Active | Active | |
| Market Availability | Discontinued | In stock | In stock | |
| REACH | REACH | REACH | REACH | |
| RoHS | RoHS | RoHS | RoHS | |
| Description | Bipolar (BJT) Transistor NPN 45 V 500 mA 250MHz 350 mW Surface Mount SOT-23-3 | Bipolar (BJT) Transistor NPN 45 V 500 mA 100MHz 300 mW Surface Mount SOT-23-3 (TO-236) | Bipolar (BJT) Transistor NPN 45 V 500 mA 250MHz 350 mW Surface Mount SST3 | |
| Manufacturer | onsemi | onsemi | Rohm Semiconductor | |
| Type | Transistors | Transistors | Transistors | |
| Datasheet | Open | Open | Open | |
| Lead Time | 49 weeks | 52 weeks | 13 weeks | |
| Country of Origin | - | - | - | |
| Export Control Class Number | EAR99 | EAR99 | EAR99 | |
| HTSUS Code | 8541.21.0075 | - | - | |
| Moisture Sensitivity Level | 1 (Unlimited) | - | - | |
| Power - Max | 350 mW | - | - | |
| Mounting Type | Surface Mount | - | - | |
| Package / Case | TO-236-3, SC-59, SOT-23-3 | - | - | |
| Transistor Type | NPN | - | - | |
| Operating Temperature | -55°C ~ 150°C (TJ) | - | - |
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Related parts
| Part | Market availability | Lifecycle | Alternatives available |
|---|---|---|---|
 MMBT3904onsemi | In stock | Obsolete | 6Alternatives availableSee Alternatives |
 MMBT2222Aonsemi | In stock | Obsolete | 4Alternatives availableSee Alternatives |
 SMBJ51Aonsemi | In stock | Active | 4Alternatives availableSee Alternatives |
| SMBJ18ADiodes Incorporated | Discontinued | Obsolete | 3Alternatives availableSee Alternatives |
 3.0SMCJ100CADiodes Incorporated | Non-stock | Active | 5Alternatives availableSee Alternatives |
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Frequently asked questions
Yes. The onsemi MMBT100A 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 MMBT100A are the BC817-40LT1G (onsemi) and the BCX19T116 (Rohm Semiconductor), out of 4 matched alternatives in total. Each is compared against the original on fit, form and function in the table above.
Partly. Some alternatives to the MMBT100A 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 MMBT100A (onsemi) is a part in the Transistors category. This page lists qualified, cross-referenced replacements for it with a side-by-side comparison.
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