Alternatives to onsemi FDW258P
onsemi FDW258P and its qualified second sources, compared on form/fit/function, stock, lifecycle and price — the same checks Parter runs inside a BOM.
 FDW258Ponsemi | DMP2021UTS-13Diodes Incorporated | SI6423ADQ-T1-GE3Vishay Siliconix | |
|---|---|---|---|
| FFF Compatibility | Shares the identical physical 8-TSSOP package size and footprint, but uses the standard industry pinout (Pins 1-3: Source, Pin 4: Gate, Pins 5-8: Drain) which differs from FDW258P's proprietary symmetric pinout (Pins 1,5,8: Drain, Pins 2,3,6,7: Source, Pin 4: Gate). PCB layout trace adjustments are required.Uses the identical standard 8-TSSOP (0.173", 4.40mm width) surface-mount package.Meets or exceeds all critical electrical ratings, including breakdown voltage (-20V vs -12V) and thermal/current capabilities. Rds(on) is slightly higher (16 mOhm max vs 11 mOhm max) but is compatible with low-voltage switching. | Shares the identical physical 8-TSSOP package size and footprint, but uses a standard single-die pinout (Pins 1,5,6: Drain, Pins 2,3,7,8: Source, Pin 4: Gate) which differs from FDW258P's symmetric layout. PCB trace layout verification is necessary.Uses the identical standard 8-TSSOP (0.173", 4.40mm width) surface-mount package.Offers superior performance with lower on-resistance and higher continuous drain current rating. Vgs max is ±8V, identical to FDW258P. | |
 AI Summary | FDW258P by onsemi: P-Channel 12 V 9A (Ta) 1.3W (Ta) Surface Mount 8-TSSOP. | An excellent modern and highly active P-channel MOSFET replacement. It offers enhanced voltage and current ratings in the same footprint, though the standard industry pinout requires trace re-routing compared to the obsolete Fairchild part.
| Provides superior electrical performance with lower RDS(on) and higher continuous drain current. Although it is in a Last Time Buy phase, it is a highly compatible transitional part, requiring minor board routing adjustments due to standard pinout differences.
|
| Lifecycle Status | Obsolete | Unknown | Unknown |
| Market Availability | In stock | Unknown | Unknown |
| REACH | Unknown | Unknown | Unknown |
| RoHS | RoHS | Unknown | Unknown |
| Description | P-Channel 12 V 9A (Ta) 1.3W (Ta) Surface Mount 8-TSSOP | An excellent modern and highly active P-channel MOSFET replacement. It offers enhanced voltage and current ratings in the same footprint, th | Provides superior electrical performance with lower RDS(on) and higher continuous drain current. Although it is in a Last Time Buy phase, it |
| Manufacturer | onsemi | Diodes Incorporated | Vishay Siliconix |
| Type | Transistors | Component | Component |
| Datasheet | Open | N/A | N/A |
| Lead Time | 7 days | Unknown | Unknown |
| Country of Origin | - | - | - |
| Export Control Class Number | EAR99 | EAR99 | EAR99 |
| HTSUS Code | 8541.21.0095 | - | - |
| Moisture Sensitivity Level | - | - | - |
| FET Type | P-Channel | - | - |
| Vgs (Max) | ±8V | - | - |
| Technology | MOSFET (Metal Oxide) | - | - |
| Mounting Type | Surface Mount | - | - |
| Package / Case | 8-TSSOP (0.173", 4.40mm Width) | - | - |
| Vgs(th) (Max) @ Id | 1.5V @ 250µA | - | - |
| Operating Temperature | -55°C ~ 150°C (TJ) | - | - |
| Rds On (Max) @ Id, Vgs | 11mOhm @ 9A, 4.5V | - | - |
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Frequently asked questions
Yes. The onsemi FDW258P 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 FDW258P are the DMP2021UTS-13 (Diodes Incorporated) and the SI6423ADQ-T1-GE3 (Vishay Siliconix). Each is compared against the original on fit, form and function in the table above.
Not always. The alternatives to the FDW258P 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 FDW258P (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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