IRFS31N20DTRLP Equivalent & Substitute Parts

Part Overview

The IRFS31N20DTRLP is an N-Channel MOSFET manufactured by Infineon Technologies, rated for 200V drain-to-source voltage with 31A continuous drain current at 25°C. This device features the HEXFET® series technology in a D2PAK surface mount package and is compliant with ROHS3 standards. The part is currently classified as obsolete, necessitating identification of functionally equivalent alternatives for ongoing design support and procurement continuity.

Substiute Parts

IRFS31N20DTRLP

Infineon TechnologiesIn Stock: 1633IRFS31N20DTRLP Datasheet

Current PartRFQ

IRFS4620TRLPBF

Infineon TechnologiesIn Stock: 16721IRFS4620TRLPBF Datasheet

MFR RecommendedRFQ

FDB2572

onsemiIn Stock: 32623FDB2572 Datasheet

MFR RecommendedRFQ

STB30NF20L

STMicroelectronicsIn Stock: 1381STB30NF20L Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the IRFS31N20DTRLP is determined by the following critical electrical and mechanical parameters:

Voltage Rating Compatibility: All substitute parts must maintain the 200V Vdss rating to ensure safe operation in the original circuit topology.

Current Handling Capacity: The 31A continuous drain current specification establishes the minimum current capability required. Substitute parts with equal or greater current ratings are acceptable.

On-State Resistance (Rds On): This parameter directly affects power dissipation and thermal performance. Lower Rds On values indicate improved efficiency and reduced heat generation.

Gate Charge and Input Capacitance: These parameters influence switching speed and gate drive requirements. Variations within acceptable ranges do not preclude substitution.

Package and Mounting: The D2PAK surface mount package is a critical mechanical requirement. All substitute parts must use identical or compatible package configurations.

Thermal Performance: Maximum power dissipation ratings must support the application's thermal requirements.

Compliance and Product Status: Active product status ensures long-term availability and supply chain reliability compared to obsolete components.

Parameter Comparison

Engineering Selection Recommendations

IRFS4620TRLPBF (Infineon Technologies): This part maintains the 200V Vdss rating and D2PAK package configuration. With 24A continuous drain current, it provides 77% of the original part's current capacity. The reduced gate charge (38 nC versus 107 nC) and lower input capacitance (1710 pF versus 2370 pF) result in faster switching characteristics. Active product status ensures supply availability. This substitute is suitable for applications where the 24A current rating is sufficient and improved switching performance is beneficial.

STB30NF20L (STMicroelectronics): This part matches the 200V Vdss rating and provides 30A continuous drain current, representing 97% of the original specification. The D2PAK package is identical. On-state resistance of 75 mOhm at 15A, 5V is superior to the original 82 mOhm specification. Active product status and AEC-Q101 automotive qualification provide long-term availability and enhanced reliability credentials. This substitute offers the closest electrical performance match to the obsolete IRFS31N20DTRLP.

FDB2572 (onsemi): This part operates at 150V Vdss, which is 25% lower than the original 200V specification. While the 29A continuous drain current closely matches the original 31A rating, the reduced voltage rating restricts its use to applications with lower voltage requirements. The superior on-state resistance (54 mOhm) and lower gate charge (34 nC) provide improved efficiency. The TO-263 (D2PAK) package is mechanically compatible. This substitute is applicable only when circuit voltage requirements do not exceed 150V.

Product Status Consideration: All three substitute parts maintain active product status, ensuring procurement continuity and long-term supply chain reliability compared to the obsolete IRFS31N20DTRLP.

Frequently Asked Questions (FAQ)

Q: Can the IRFS4620TRLPBF replace the IRFS31N20DTRLP in all applications?

A: The IRFS4620TRLPBF is suitable for applications where the 24A continuous drain current rating is adequate. If the original design requires the full 31A capability, this substitute may not be appropriate. Both parts share the 200V Vdss rating and D2PAK package, ensuring electrical and mechanical compatibility in voltage-limited designs.

Q: What is the primary advantage of the STB30NF20L over the IRFS31N20DTRLP?

A: The STB30NF20L provides 30A continuous drain current (97% of original), matching the 200V Vdss rating and D2PAK package. The on-state resistance of 75 mOhm is lower than the original 82 mOhm, resulting in reduced power dissipation. Active product status and AEC-Q101 automotive qualification provide enhanced supply reliability and quality assurance.

Q: Why is the FDB2572 limited to 150V applications?

A: The FDB2572 is rated for 150V Vdss, which is 25% lower than the original 200V specification. Using this part in a 200V circuit would exceed its voltage rating and create reliability and safety risks. This substitute is restricted to applications with maximum operating voltages of 150V or lower.

Q: Are all substitute parts in the same D2PAK package?

A: Yes. The IRFS31N20DTRLP, IRFS4620TRLPBF, FDB2572, and STB30NF20L all use D2PAK (TO-263-3) surface mount packages. This ensures mechanical compatibility and identical PCB footprints, simplifying design transitions.

Q: How do gate charge differences affect circuit performance?

A: Gate charge (Qg) determines the energy required to switch the MOSFET on and off. The IRFS31N20DTRLP requires 107 nC, while the IRFS4620TRLPBF requires only 38 nC. Lower gate charge enables faster switching and reduces gate drive power consumption. If the original gate driver is designed for the higher charge requirement, the substitute with lower gate charge will operate reliably with improved efficiency.

Q: What does RoHS3 compliance mean for these parts?

A: ROHS3 compliance indicates that all substitute parts meet Restriction of Hazardous Substances Directive requirements, restricting lead, cadmium, mercury, and other hazardous materials. This ensures environmental compliance and compatibility with modern manufacturing and end-of-life recycling standards.

Q: Can the IRFS31N20DTRLP be used interchangeably with these substitutes in existing designs?

A: Direct interchangeability depends on application-specific current and voltage requirements. The STB30NF20L offers the closest electrical match (30A at 200V). The IRFS4620TRLPBF is suitable for designs requiring 24A or less at 200V. The FDB2572 is limited to 150V maximum applications. All three maintain identical D2PAK packages and operating temperature ranges, supporting mechanical and thermal compatibility.