Alternatives to Littelfuse SP0503BAHT
Littelfuse SP0503BAHT and its qualified second sources, compared on form/fit/function, stock, lifecycle and price — the same checks Parter runs inside a BOM.
SP0503BAHTLittelfuse | SP0503BAHTGLittelfuse Inc. | SP0504BAHTGLittelfuse Inc. | +2more | |
|---|---|---|---|---|
| FFF Compatibility | Identical pinout (Pin 1 GND, Pins 2-4 I/O) and SOT-143-4 package foot-print.Identical physical SOT-143 package dimensions and mounting style.Identical 3-channel unidirectional TVS configuration, 5.5V reverse standoff voltage, and 8.5V clamping voltage. | Requires a PCB redesign from the SOT-143-4 footprint to a SOT-23-5 footprint.SOT-23-5 package has a completely different body shape, lead frame, and footprint than SOT-143.Maintains the same 5.5V standoff, 8.5V clamping, and unidirectional channel characteristics, with one extra channel. | ||
SP0503BAHT by Littelfuse: 8.5V Clamp Ipp Tvs Diode Surface Mount SOT-143-4. | This is the official direct replacement designated by Littelfuse. It transitions the obsolete part to a lead-free, RoHS-compliant green version while maintaining identical physical and electrical specifications.
| A sibling variant from the same SP05 family, this device offers 4 ESD protection channels in a standard SOT-23-5 package. It is an excellent choice if the PCB is undergoing a redesign and a more standard package is desired.
| ||
| Lifecycle Status | Obsolete | Active | Active | |
| Market Availability | Discontinued | In stock | In stock | |
| REACH | Unknown | REACH | REACH | |
| RoHS | RoHS | RoHS | RoHS | |
| Description | 8.5V Clamp Ipp Tvs Diode Surface Mount SOT-143-4 | 8.5V Clamp Ipp Tvs Diode Surface Mount SOT-143-4 | 8.5V Clamp Ipp Tvs Diode Surface Mount SOT-23-5 | |
| Manufacturer | Littelfuse | Littelfuse Inc. | Littelfuse Inc. | |
| Type | Transient Voltage Suppressors (TVS) | Transient Voltage Suppressors (TVS) | Transient Voltage Suppressors (TVS) | |
| Datasheet | Open | Open | Open | |
| Lead Time | Unknown | 21 weeks | 13 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 | TO-253-4, TO-253AA | - | - | |
| Operating Temperature | -40°C ~ 85°C (TA) | - | - | |
| Power Line Protection | No | - | - | |
| Supplier Device Package | SOT-143-4 | - | - | |
| Unidirectional Channels | 3 | - | - |
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Frequently asked questions
Yes. The Littelfuse SP0503BAHT 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 Littelfuse SP0503BAHT are the SP0503BAHTG (Littelfuse Inc.) and the SP0504BAHTG (Littelfuse Inc.), out of 4 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 SP0503BAHT 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 SP0503BAHT (Littelfuse) 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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