AUIRFS8408 N-Channel 40V 195A MOSFET Equivalent & Substitute Parts

Part Overview

The AUIRFS8408 is an N-Channel MOSFET manufactured by Infineon Technologies, rated for 40V drain-to-source voltage with 195A continuous drain current in a D2PAK surface mount package. This device is part of the HEXFET® series and is classified as obsolete. Due to its obsolete status, equivalent and substitute parts are necessary to maintain design continuity and ensure component availability for new production runs and field replacements.

Substiute Parts

AUIRFS8408

Infineon TechnologiesIn Stock: 1934AUIRFS8408 Datasheet

Current PartRFQ

AUIRFS3107TRL

Infineon TechnologiesIn Stock: 1000169AUIRFS3107TRL Datasheet

MFR RecommendedRFQ

IPB120N04S401ATMA1

Infineon TechnologiesIn Stock: 16836IPB120N04S401ATMA1 Datasheet

MFR RecommendedRFQ

CSD18510KTTT

Texas InstrumentsIn Stock: 1490CSD18510KTTT Datasheet

MFR RecommendedRFQ

FDB9406-F085

onsemiIn Stock: 2908FDB9406-F085 Datasheet

MFR RecommendedRFQ

NP109N04PUK-E1-AY

Renesas Electronics CorporationIn Stock: 55313NP109N04PUK-E1-AY Datasheet

MFR RecommendedRFQ

NP110N04PUG-E1-AY

Renesas Electronics CorporationIn Stock: 1263NP110N04PUG-E1-AY Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AUIRFS8408 is determined by the following critical electrical and mechanical parameters:

Primary Substitution Criteria:

• Drain-to-Source Voltage (Vdss): Must be ≥40V to maintain voltage margin
• Continuous Drain Current (Id): Must be ≥195A to support the same load conditions
• On-Resistance (Rds On): Lower or equivalent values ensure thermal performance
• Package Type: D2PAK (TO-263-3) surface mount configuration for PCB compatibility
• Operating Temperature Range: -55°C to 175°C (TJ) minimum
• Gate Drive Voltage: 10V standard drive voltage compatibility

Substitution Groups:

Group 1: Direct Voltage/Current Equivalents (40V, ≥195A) Parts maintaining 40V Vdss with ≥195A continuous drain current in D2PAK package. These provide direct functional replacement with comparable thermal characteristics.

Group 2: Higher Voltage Rated Parts (≥40V, ≥195A) Parts with higher Vdss ratings (e.g., 75V) but maintaining ≥195A current rating. These provide enhanced voltage margin and are electrically compatible in 40V applications.

Group 3: Lower Current Rated Parts (40V, <195A) Parts with 40V Vdss but lower current ratings (110A–120A). These are suitable only for applications where the actual operating current is below the substitute part's rating.

Group 4: Higher Current Density Parts (40V, >195A) Parts with superior current handling (e.g., 274A) in the same voltage class. These provide thermal headroom and reduced on-resistance.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Equivalent Current Rating):

The AUIRFS3107TRL (Infineon) is the manufacturer-recommended substitute. Although rated at 75V Vdss (higher than the original 40V), it maintains the same 195A continuous drain current and D2PAK package. The higher voltage rating provides additional design margin in 40V applications. However, this part is classified as Last Time Buy, indicating limited future availability.

The CSD18510KTTT (Texas Instruments) offers superior current handling at 274A with 40V Vdss and is currently Active. This part provides thermal headroom and lower gate charge, making it suitable for applications requiring enhanced performance margins. The on-resistance is slightly higher (2.6 mOhm vs. 1.6 mOhm), which must be evaluated against thermal budget constraints.

For Current-Limited Applications:

The IPB120N04S401ATMA1 (Infineon OptiMOS™ series) is rated for 120A continuous drain current at 40V Vdss. This part is suitable only for applications where the actual operating current does not exceed 120A. It features lower on-resistance (1.5 mOhm) and reduced gate charge (176 nC), resulting in lower power dissipation (188W). This part is currently Active with RoHS3 compliance.

The NP109N04PUK-E1-AY and NP110N04PUG-E1-AY (Renesas) are both rated for 110A continuous drain current at 40V Vdss and are currently Active. These parts are suitable for applications with maximum operating currents below 110A. The NP109N04PUK-E1-AY features lower gate charge (189 nC) compared to the NP110N04PUG-E1-AY (390 nC).

Compliance and Availability:

All recommended active substitutes comply with RoHS3 and REACH regulations. The AUIRFS3107TRL and CSD18510KTTT are manufacturer-recommended parts with established supply chains. For new designs, CSD18510KTTT is preferred due to its Active status and superior current rating. For existing designs requiring exact current matching, AUIRFS3107TRL provides the closest electrical equivalent.

Frequently Asked Questions (FAQ)

Q1: Can the AUIRFS3107TRL replace the AUIRFS8408 in a 40V application?

A: Yes. The AUIRFS3107TRL is rated for 75V Vdss, which is higher than the 40V requirement of the original circuit. In a 40V application, the higher voltage rating provides additional design margin without affecting circuit operation. Both parts maintain 195A continuous drain current and use the same D2PAK package. However, verify that the higher on-resistance (3.0 mOhm vs. 1.6 mOhm) does not exceed thermal budget constraints.

Q2: Why is the CSD18510KTTT rated for 274A when the original part is 195A?

A: The CSD18510KTTT is a higher-performance device from Texas Instruments' NexFET™ series. The 274A rating reflects superior current-handling capability in the same 40V voltage class and D2PAK package. This higher current rating provides thermal headroom and allows operation at lower junction temperatures for the same power dissipation. The on-resistance is 2.6 mOhm compared to 1.6 mOhm in the original part, which must be factored into thermal calculations.

Q3: Can I use the IPB120N04S401ATMA1 as a direct replacement?

A: The IPB120N04S401ATMA1 can replace the AUIRFS8408 only if the actual operating drain current in your application does not exceed 120A. This part is rated for 120A continuous drain current, which is 75A lower than the original 195A rating. If your circuit operates at currents above 120A, this part will exceed its continuous current rating and may fail. Verify actual operating current before substitution.

Q4: What is the difference between the NP109N04PUK-E1-AY and NP110N04PUG-E1-AY?

A: Both Renesas parts are rated for 40V Vdss and 110A continuous drain current in D2PAK packages. The primary difference is gate charge: the NP109N04PUK-E1-AY has 189 nC while the NP110N04PUG-E1-AY has 390 nC. The lower gate charge in the NP109N04PUK-E1-AY results in faster switching and lower drive power requirements. Select based on gate drive circuit capability and switching frequency requirements.

Q5: Are all substitute parts RoHS3 compliant?

A: All active substitute parts listed (IPB120N04S401ATMA1, CSD18510KTTT, NP109N04PUK-E1-AY, NP110N04PUG-E1-AY) are RoHS3 compliant. The AUIRFS3107TRL is Last Time Buy status and FDB9406-F085 is obsolete; verify RoHS compliance status with your supplier before procurement.

Q6: Do all substitute parts use the same D2PAK package?

A: Yes. All substitute parts listed use the D2PAK (TO-263-3) surface mount package with 2 leads plus tab configuration. This ensures PCB footprint compatibility without layout modifications. Verify package marking and lead configuration with the supplier datasheet before assembly.

Q7: What is the moisture sensitivity level (MSL) for these parts?

A: All substitute parts are rated MSL 1 (Unlimited) except the CSD18510KTTT, which is rated MSL 2 (1 Year). MSL 1 parts have no moisture sensitivity restrictions. MSL 2 parts require storage in dry conditions and have a one-year shelf life from the date of manufacture. Verify storage conditions and shelf life with your supplier.

Q8: Which substitute part should I select for a new design?

A: For new designs, the CSD18510KTTT (Texas Instruments) is recommended. It is currently Active, offers superior current rating (274A), lower gate charge (132 nC), and is RoHS3 compliant. If exact current matching is required, the AUIRFS3107TRL provides 195A rating but is Last Time Buy status. For cost-optimized designs with lower current requirements, the IPB120N04S401ATMA1 offers the lowest power dissipation (188W) and is currently Active.