IRF3711 Equivalent & Substitute Parts

Part Overview

The IRF3711 is an N-Channel MOSFET manufactured by Infineon Technologies, rated for 20V drain-to-source voltage with 110A continuous drain current in a Through Hole TO-220AB package. This device is classified as Obsolete, making identification of functionally equivalent alternatives necessary for ongoing production and maintenance applications. The HEXFET® series component delivers 3.1W power dissipation at ambient temperature and 120W at case temperature, suitable for switching and power management circuits requiring moderate voltage and high current handling.

Substiute Parts

IRF3711

Infineon TechnologiesIn Stock: 28962IRF3711 Datasheet

Current PartRFQ

STP90NF03L

STMicroelectronicsIn Stock: 35428STP90NF03L Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the IRF3711 is determined by the following critical electrical and mechanical parameters:

Primary Substitution Criteria:

• FET Type: N-Channel MOSFET technology
• Package: Through Hole TO-220 form factor (mechanical compatibility)
• Drain-to-Source Voltage (Vdss): Equal to or greater than 20V
• Continuous Drain Current (Id): Equal to or greater than 110A at 25°C
• On-State Resistance (Rds On): Equal to or lower than 6mOhm at specified gate voltage
• Gate Threshold Voltage (Vgs(th)): Within compatible range for drive circuit compatibility
• Operating Temperature Range: Minimum -55°C to maximum 150°C or broader

The STP90NF03L from STMicroelectronics meets the mechanical packaging requirement (TO-220-3) and maintains N-Channel MOSFET technology. However, this substitute exhibits a higher Vdss rating (30V versus 20V) and lower continuous drain current (90A versus 110A), representing a trade-off in voltage headroom against reduced current capacity. The Rds On specification (6.5mOhm at 45A, 10V) remains within acceptable substitution parameters for applications not requiring the full 110A rating.

Parameter Comparison

Engineering Selection Recommendations

Substitution Feasibility:

The STP90NF03L serves as a functional substitute for the IRF3711 in applications where the continuous drain current requirement does not exceed 90A. The higher Vdss rating (30V) provides additional voltage margin in circuits operating below 20V, reducing stress on the device during transient conditions.

Product Status Considerations:

The IRF3711 is classified as Obsolete, while the STP90NF03L is classified as Not For New Designs. Both statuses indicate limited availability and manufacturer support. For new product development, neither part is recommended; alternative current-generation N-Channel MOSFETs with similar electrical specifications should be evaluated.

Compliance and Certification:

The IRF3711 is RoHS non-compliant, while the STP90NF03L achieves ROHS3 compliance. Both parts are REACH Unaffected and carry EAR99 export classification. Applications subject to RoHS requirements must use the STP90NF03L or identify alternative compliant devices.

Current Derating:

Applications requiring the full 110A continuous drain current of the IRF3711 cannot use the STP90NF03L without circuit redesign or thermal management modifications, as the substitute is rated for 90A maximum.

Frequently Asked Questions (FAQ)

Q: Can the STP90NF03L directly replace the IRF3711 in all applications?

A: Direct replacement is limited to applications where continuous drain current does not exceed 90A. The STP90NF03L's higher Vdss rating (30V versus 20V) is compatible with circuits designed for 20V operation. Gate drive voltage compatibility must be verified; the STP90NF03L has a lower gate threshold voltage (2.5V versus 3V), which may affect switching characteristics in marginal drive conditions.

Q: What is the impact of the lower continuous drain current rating of the STP90NF03L?

A: The STP90NF03L is rated for 90A continuous drain current compared to the IRF3711's 110A. In applications operating near or above 90A, the substitute will experience higher junction temperatures and reduced thermal margin. Thermal analysis of the specific application is required to determine if the 150W power dissipation rating of the STP90NF03L provides adequate headroom.

Q: Are there mechanical compatibility issues between these parts?

A: Both devices use the TO-220-3 package and are Through Hole mounted. Pin configuration and lead spacing are identical, allowing direct PCB footprint compatibility without layout modifications.

Q: How do the gate charge specifications affect circuit design?

A: The STP90NF03L exhibits slightly higher gate charge (47nC at 5V versus 44nC at 4.5V for the IRF3711). This difference is within typical gate driver capability margins and does not require circuit redesign for standard switching applications. High-frequency switching circuits should verify gate driver current capacity.

Q: What is the significance of the different gate threshold voltages?

A: The STP90NF03L has a lower gate threshold voltage (2.5V versus 3V). This allows the device to turn on at lower gate voltages, potentially improving switching speed in circuits with limited gate drive voltage. However, this also increases the risk of unintended turn-on from noise or transients in marginal drive conditions.

Q: Should I use the STP90NF03L for new designs?

A: No. The STP90NF03L is classified as Not For New Designs. Current-generation N-Channel MOSFETs with equivalent or superior electrical specifications should be selected for new product development to ensure long-term availability and manufacturer support.

Q: What compliance advantages does the STP90NF03L offer?

A: The STP90NF03L achieves ROHS3 compliance, while the IRF3711 is RoHS non-compliant. For applications subject to RoHS directives, the STP90NF03L is the only viable option between these two parts. Both are REACH Unaffected.