Alternatives to onsemi 1SMB18CAT3
onsemi 1SMB18CAT3 and its qualified second sources, compared on form/fit/function, stock, lifecycle and price — the same checks Parter runs inside a BOM.
 1SMB18CAT3onsemi |  SMBJ18CALittelfuse Inc. |  SMBJ18CA-TRSTMicroelectronics | +5more | |
|---|---|---|---|---|
| FFF Compatibility | Both parts use the DO-214AA (SMB) surface-mount package with standard 2-terminal layouts and land patterns.Identical physical package and package height profiles.Meets or exceeds all electrical parameters including 18V standoff, 20V min breakdown, and 29.2V maximum clamping voltage. | Standard DO-214AA (SMB) package footprint is a direct 1:1 match.Standard physical dimensions match the target device.Offers equivalent standoff (18V) and clamping (29.2V) parameters, with a slightly improved surge current handling capacity. | ||
 AI Summary | 1SMB18CAT3 by onsemi: 29.2V Clamp 20.5A Ipp Tvs Diode Surface Mount SMB. | The Littelfuse SMBJ18CA is an industry-standard bidirectional TVS diode that acts as a direct, drop-in replacement for the obsolete 1SMB18CAT3. It provides matching electrical protections with identical clamping characteristics in an active, long-term lifecycle product.
| STMicroelectronics' SMBJ18CA-TR provides a highly robust alternative with a slightly higher peak pulse current handling capability of 21.5A compared to the original 20.5A. It serves as a direct drop-in second-source option.
| |
| Lifecycle Status | Obsolete | Active | Active | |
| Market Availability | Discontinued | In stock | In stock | |
| REACH | REACH | REACH | REACH | |
| RoHS | RoHS | RoHS | RoHS | |
| Description | 29.2V Clamp 20.5A Ipp Tvs Diode Surface Mount SMB | 29.2V Clamp 20.6A Ipp Tvs Diode Surface Mount DO-214AA (SMBJ) | 29.2V Clamp 21.5A Ipp Tvs Diode Surface Mount SMB | |
| Manufacturer | onsemi | Littelfuse Inc. | STMicroelectronics | |
| Type | Transient Voltage Suppressors (TVS) | Transient Voltage Suppressors (TVS) | Transient Voltage Suppressors (TVS) | |
| Datasheet | Open | Open | Open | |
| Lead Time | Unknown | 14 weeks | 16 weeks | |
| Country of Origin | - | - | - | |
| Export Control Class Number | EAR99 | EAR99 | EAR99 | |
| HTSUS Code | 8541.10.0080 | - | - | |
| Moisture Sensitivity Level | 1 (Unlimited) | - | - | |
| Type | Zener | - | - | |
| Applications | General Purpose | - | - | |
| Mounting Type | Surface Mount | - | - | |
| Package / Case | DO-214AA, SMB | - | - | |
| Power - Peak Pulse | 600W | - | - | |
| Operating Temperature | -65°C ~ 150°C (TJ) | - | - | |
| Power Line Protection | No | - | - | |
| Bidirectional Channels | 1 | - | - |
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Related parts
| Part | Market availability | Lifecycle | Alternatives available |
|---|---|---|---|
 1SMB18CAT3GLittelfuse | Discontinued | Obsolete | 7Alternatives availableSee Alternatives |
| 1SMB58CAT3GLittelfuse | Discontinued | Obsolete | 6Alternatives availableSee Alternatives |
 1SMB48AT3GLittelfuse | Discontinued | Obsolete | 9Alternatives availableSee Alternatives |
| 1SMB51AT3GLittelfuse | Discontinued | Obsolete | 6Alternatives availableSee Alternatives |
 1SMC18AT3GLittelfuse | Discontinued | Obsolete | 5Alternatives availableSee Alternatives |
 1SMB24AT3onsemi | Discontinued | Obsolete | 5Alternatives availableSee Alternatives |
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Frequently asked questions
Yes. The onsemi 1SMB18CAT3 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 1SMB18CAT3 are the SMBJ18CA (Littelfuse Inc.) and the SMBJ18CA-TR (STMicroelectronics), out of 7 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 1SMB18CAT3 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 1SMB18CAT3 (onsemi) is a part in the Transient Voltage Suppressors (TVS) category. This page lists qualified, cross-referenced replacements for it with a side-by-side comparison.
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