Alternatives to onsemi BSS138LT1
onsemi BSS138LT1 and its qualified second sources, compared on form/fit/function, stock, lifecycle and price — the same checks Parter runs inside a BOM.
 BSS138LT1onsemi |  BSS138LT1Gonsemi |  BSS138onsemi | +2more | |
|---|---|---|---|---|
| FFF Compatibility | Pin-compatible drop-in with identical pin numbers, names, and functions (Pin 1: Gate, Pin 2: Source, Pin 3: Drain).Identical SOT-23 (TO-236) dimensions and surface mount style.Matches all electrical characteristics including Vdss of 50V, continuous drain current of 200mA, and gate-source threshold. | Pinout assignments are identical (Pin 1: Gate, Pin 2: Source, Pin 3: Drain), but the pin naming convention differs slightly (e.g., G/S/D vs GATE/SOURCE/DRAIN).Housed in the identical SOT-23 package with the same PCB footprint requirements.Key electrical parameters meet or exceed the original with 50V Vdss and 220mA Id. | ||
 AI Summary | BSS138LT1 by onsemi: N-Channel 50 V 200mA (Ta) Surface Mount SOT-23-3 (TO-236). | The BSS138LT1G is the direct RoHS-compliant successor to the obsolete BSS138LT1. It offers identical electrical parameters, package dimensions, and pin configurations, making it a perfect drop-in replacement.
| The BSS138 is an active, highly popular sibling variant from onsemi that offers slightly better current handling (220mA) and lower on-resistance (3.0 Ohm). It is fully compatible with the same SOT-23 footprint.
| |
| Lifecycle Status | Obsolete | Active | Active | |
| Market Availability | Discontinued | In stock | In stock | |
| REACH | REACH | REACH | REACH | |
| RoHS | RoHS | RoHS | RoHS | |
| Description | N-Channel 50 V 200mA (Ta) Surface Mount SOT-23-3 (TO-236) | N-Channel 50 V 200mA (Ta) 225mW (Ta) Surface Mount SOT-23-3 (TO-236) | N-Channel 50 V 220mA (Tj) 430mW Surface Mount SOT-23 | |
| Manufacturer | onsemi | onsemi | onsemi | |
| Type | Transistors | Transistors | Transistors | |
| Datasheet | Open | Open | Open | |
| Lead Time | 17 weeks | 53 weeks | 16 weeks | |
| Country of Origin | - | - | - | |
| Export Control Class Number | EAR99 | EAR99 | EAR99 | |
| HTSUS Code | 8541.29.0095 | - | - | |
| Moisture Sensitivity Level | 1 (Unlimited) | - | - | |
| FET Type | N-Channel | - | - | |
| Technology | MOSFET (Metal Oxide) | - | - | |
| Mounting Type | Surface Mount | - | - | |
| Package / Case | TO-236-3, SC-59, SOT-23-3 | - | - | |
| Vgs(th) (Max) @ Id | 1.5V @ 1mA | - | - |
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Related parts
| Part | Market availability | Lifecycle | Alternatives available |
|---|---|---|---|
 BSS138_NLonsemi | Discontinued | Obsolete | 5Alternatives availableSee Alternatives |
 BSS138onsemi | In stock | Active | 5Alternatives availableSee Alternatives |
 BSS84Diodes Incorporated | Non-stock | Active | 6Alternatives availableSee Alternatives |
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Frequently asked questions
Yes. The onsemi BSS138LT1 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 BSS138LT1 are the BSS138LT1G (onsemi) and the BSS138 (onsemi), 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 BSS138LT1 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 BSS138LT1 (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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