NDS9955 Equivalent & Substitute Parts

Part Overview

The NDS9955 is a dual N-channel MOSFET array manufactured by onsemi, rated for 50V drain-to-source voltage and 3A continuous drain current in an 8-SOIC surface mount package. This device is classified as obsolete, necessitating identification of equivalent and substitute components for ongoing design support and procurement.

Substiute Parts

NDS9955

onsemiIn Stock: 2437NDS9955 Datasheet

Current PartRFQ

FDS9945

onsemiIn Stock: 16496FDS9945 Datasheet

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IRF7103TRPBF

Infineon TechnologiesIn Stock: 17412IRF7103TRPBF Datasheet

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AUIRF7103QTR

Infineon TechnologiesIn Stock: 19760AUIRF7103QTR Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the NDS9955 is determined by electrical and mechanical compatibility across the following critical parameters:

Electrical Compatibility Criteria:

• Configuration: Dual N-channel MOSFET array
• Drain-to-source voltage rating (Vdss): Minimum 50V
• Continuous drain current (Id): Minimum 3A at 25°C
• On-state resistance (Rds On): Maximum 130mOhm @ 3A, 10V
• Gate threshold voltage (Vgs(th)): Maximum 3V @ 250µA
• Gate charge (Qg): Maximum 30nC @ 10V
• Input capacitance (Ciss): Maximum 345pF @ 25V

Mechanical Compatibility Criteria:

• Package type: 8-SOIC surface mount
• Package dimensions: 0.154" width (3.90mm)

Substitute parts must meet or exceed all electrical parameters while maintaining identical package specifications. Parts with higher voltage ratings, lower on-state resistance, or improved thermal performance are acceptable substitutes provided they maintain the same pinout and package footprint.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: FDS9945

The FDS9945 is the recommended direct substitute for the NDS9955. Both devices are manufactured by onsemi and share identical pinout and package specifications. The FDS9945 exceeds the electrical requirements of the NDS9955 with a higher voltage rating (60V vs. 50V), increased current capability (3.5A vs. 3A), and improved on-state resistance (100mOhm vs. 130mOhm). The FDS9945 is currently in active production status with ROHS3 compliance, addressing the obsolescence and regulatory limitations of the NDS9955.

Alternative Substitute: IRF7103TRPBF

The IRF7103TRPBF, manufactured by Infineon Technologies, provides electrical equivalence to the NDS9955 with identical Vdss (50V), Id (3A), and Rds On (130mOhm) specifications. This device is in active production status with ROHS3 compliance. The IRF7103TRPBF offers superior thermal performance (2W vs. 900mW maximum power dissipation) and lower input capacitance (290pF vs. 345pF), making it suitable for applications requiring enhanced thermal margin or faster switching characteristics.

Secondary Alternative: AUIRF7103QTR

The AUIRF7103QTR is an automotive-grade variant of the IRF7103 series, qualified to AEC-Q101 standards. This device matches the electrical specifications of the NDS9955 and provides the highest thermal performance (2.4W maximum power dissipation) among available substitutes. The AUIRF7103QTR is classified as obsolete; however, it remains available in inventory. This option is suitable for applications requiring automotive qualification or extended temperature range operation (-55°C to 175°C).

Frequently Asked Questions (FAQ)

Q: Can the FDS9945 be used as a direct replacement for the NDS9955?

A: Yes. The FDS9945 is a direct substitute with identical pinout, package footprint (8-SOIC), and mounting type. All electrical parameters of the FDS9945 meet or exceed the NDS9955 specifications. No circuit modifications are required.

Q: What is the primary advantage of using IRF7103TRPBF over FDS9945?

A: The IRF7103TRPBF provides superior thermal performance with a maximum power dissipation rating of 2W compared to the FDS9945 at 1W. Additionally, the IRF7103TRPBF exhibits lower input capacitance (290pF vs. 420pF), which may benefit applications with stringent switching speed requirements. Both devices are in active production with ROHS3 compliance.

Q: Are there package compatibility concerns when substituting these parts?

A: All substitute parts listed maintain the 8-SOIC package specification with identical 0.154" (3.90mm) width. PCB footprints and assembly processes require no modification. Pinout compatibility is maintained across all substitutes.

Q: Why is the NDS9955 classified as obsolete?

A: The NDS9955 is no longer in active production. The FDS9945 represents the current onsemi product line continuation with enhanced electrical performance and regulatory compliance (ROHS3).

Q: Which substitute is recommended for new designs?

A: The FDS9945 is recommended for new designs. It is in active production status, offers improved electrical performance, and maintains full compatibility with existing NDS9955 designs. ROHS3 compliance ensures regulatory alignment with current environmental standards.

Q: Can AUIRF7103QTR be used in non-automotive applications?

A: Yes. The AUIRF7103QTR meets all electrical requirements for the NDS9955 and exceeds performance specifications. Automotive qualification does not restrict use in non-automotive applications. However, the AUIRF7103QTR is classified as obsolete; the FDS9945 or IRF7103TRPBF are preferred for new procurement.

Q: What is the difference between IRF7103TRPBF and AUIRF7103QTR?

A: Both devices share identical electrical specifications and package type. The AUIRF7103QTR is automotive-grade with AEC-Q101 qualification and operates across an extended temperature range (-55°C to 175°C vs. -55°C to 150°C). The AUIRF7103QTR has higher maximum power dissipation (2.4W vs. 2W). The IRF7103TRPBF is in active production; the AUIRF7103QTR is obsolete.

Q: Are all substitutes RoHS compliant?

A: The NDS9955 is RoHS non-compliant. All substitute parts (FDS9945, IRF7103TRPBF, and AUIRF7103QTR) are ROHS3 compliant, meeting current environmental regulations for new designs and procurement.