IRFS33N15DPBF Equivalent & Substitute Parts

Part Overview

The IRFS33N15DPBF is an N-Channel MOSFET manufactured by Infineon Technologies, rated for 150V drain-to-source voltage with 33A continuous drain current at 25°C. This device is housed in a D2PAK (TO-263-3) surface mount package and belongs to the HEXFET® series. The part is classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing design support and procurement continuity.

Substiute Parts

IRFS33N15DPBF

Infineon TechnologiesIn Stock: 2459IRFS33N15DPBF Datasheet

Current PartRFQ

FDB2572

onsemiIn Stock: 32623FDB2572 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the IRFS33N15DPBF is determined by strict equivalence across the following electrical and mechanical parameters:

Critical Matching Parameters:

• Drain-to-Source Voltage (Vdss): 150V minimum
• Package Type: D2PAK (TO-263-3) surface mount configuration
• FET Technology: N-Channel MOSFET
• Operating Temperature Range: -55°C to 175°C (TJ)

Functional Compatibility Parameters:

• Continuous Drain Current (Id): Must support minimum 29A at Tc to maintain circuit performance margin
• On-State Resistance (Rds On): Must not exceed 56mOhm at rated conditions to preserve thermal and efficiency characteristics
• Gate Threshold Voltage (Vgs(th)): Must fall within acceptable gate drive voltage compatibility range
• Gate Charge (Qg): Lower values reduce switching losses; values up to 90nC are acceptable

The FDB2572 from onsemi meets all critical matching parameters and functional compatibility requirements, qualifying it as a direct substitute for the obsolete IRFS33N15DPBF.

Parameter Comparison

Engineering Selection Recommendations

The FDB2572 is the qualified substitute for the obsolete IRFS33N15DPBF based on the following engineering criteria:

Voltage and Package Compatibility: Both devices share identical 150V Vdss ratings and D2PAK (TO-263-3) surface mount packaging, ensuring direct PCB footprint compatibility without layout modifications.

Current Handling: The FDB2572 delivers 29A continuous drain current at Tc, which is 88% of the original 33A specification. This margin is acceptable for most applications where the IRFS33N15DPBF was specified, provided circuit design does not depend on the full 33A capacity.

On-State Resistance: The FDB2572 exhibits 54mOhm Rds On compared to 56mOhm in the original part, representing a 3.6% improvement in conduction efficiency. This favorable characteristic reduces power dissipation and thermal stress.

Switching Characteristics: The FDB2572 features significantly lower gate charge (34nC versus 90nC) and input capacitance (1770pF versus 2020pF), resulting in reduced switching losses and improved high-frequency performance.

Regulatory and Supply Status: The FDB2572 is active in production with ROHS3 compliance certification, ensuring long-term availability and regulatory alignment. The original IRFS33N15DPBF is obsolete, making the FDB2572 the necessary alternative for new designs and ongoing procurement.

Gate Drive Voltage Consideration: The FDB2572 has a maximum Vgs rating of ±20V compared to ±30V for the original part. Verify that existing gate drive circuits do not exceed ±20V to ensure safe operation.

Frequently Asked Questions (FAQ)

Q: Can the FDB2572 be used as a direct replacement for the IRFS33N15DPBF without PCB modifications?

A: Yes. Both devices use identical D2PAK (TO-263-3) surface mount packaging with the same pinout and footprint. No PCB layout changes are required for mechanical and electrical connection.

Q: What is the impact of the 4A difference in continuous drain current (33A versus 29A)?

A: The FDB2572 provides 88% of the original current rating. For applications operating below 29A, there is no functional impact. For circuits requiring the full 33A capacity, thermal analysis and current distribution verification are necessary to confirm the substitute remains within safe operating limits.

Q: Are the gate drive voltage requirements compatible between these two devices?

A: The FDB2572 has a lower maximum gate voltage rating (±20V versus ±30V). Confirm that your gate drive circuit does not exceed ±20V. Both devices have similar gate threshold voltages (5.5V versus 4.0V), which may require minor gate drive timing adjustments in high-speed switching applications.

Q: Does the lower gate charge of the FDB2572 affect circuit performance?

A: The FDB2572 gate charge is 34nC compared to 90nC in the original part. This reduction decreases switching losses and improves efficiency, particularly in high-frequency applications. No negative performance impact is expected; improved switching characteristics are typical benefits of this substitution.

Q: What compliance certifications apply to the FDB2572?

A: The FDB2572 is ROHS3 compliant and REACH unaffected, meeting current environmental and regulatory requirements. The original IRFS33N15DPBF is classified as obsolete, making the FDB2572 the compliant alternative for new designs.

Q: Is the FDB2572 available in the same packaging options as the original part?

A: The FDB2572 is supplied in Cut Tape (CT) and Digi-Reel® packaging formats. Both devices use the D2PAK (TO-263-3) surface mount package. Verify packaging format availability with your supplier to match your assembly requirements.