IRF740ASTRR Equivalent & Substitute Parts

Part Overview

The IRF740ASTRR is an N-Channel MOSFET manufactured by Vishay Siliconix, rated for 400V drain-to-source voltage with 10A continuous drain current in a surface mount TO-263 (D2PAK) package. This device is classified as obsolete, necessitating identification of equivalent and substitute components for ongoing design support and procurement. Substitute parts must maintain electrical and mechanical compatibility within the specified parameter ranges to ensure functional equivalence in circuit applications.

Substiute Parts

IRF740ASTRR

Vishay SiliconixIn Stock: 945IRF740ASTRR Datasheet

Current PartRFQ

IRF740ASTRRPBF

Vishay SiliconixIn Stock: 2769IRF740ASTRRPBF Datasheet

DirectRFQ

STB11NK40ZT4

STMicroelectronicsIn Stock: 2395STB11NK40ZT4 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the IRF740ASTRR are identified based on strict electrical and mechanical parameter compatibility. The primary substitution criteria are:

Critical Parameters for Substitution:

• Drain-to-Source Voltage (Vdss): 400 V minimum
• Continuous Drain Current (Id): 10 A or greater
• On-State Resistance (Rds On): 550 mOhm or lower at rated conditions
• Package Type: TO-263 (D2PAK) surface mount configuration
• FET Type: N-Channel MOSFET
• Operating Temperature Range: -55°C to 150°C or greater

Substitute parts are grouped into two categories:

Direct Manufacturer Equivalent: IRF740ASTRRPBF maintains identical electrical specifications and differs only in packaging format (Tape & Reel versus bulk). This part is functionally interchangeable with the main part number.

Cross-Manufacturer Substitute: STB11NK40ZT4 (STMicroelectronics) meets the core voltage and package requirements with comparable on-state resistance and operating temperature range. Minor parameter variations exist within acceptable engineering tolerances for the specified application class.

Parameter Comparison

Engineering Selection Recommendations

IRF740ASTRRPBF (Vishay Siliconix): This part is the primary direct equivalent for the obsolete IRF740ASTRR. It maintains identical electrical specifications and is available in active product status with ROHS3 compliance. The only distinction is packaging format (Tape & Reel). This part is suitable for direct substitution in all applications where the IRF740ASTRR was specified.

STB11NK40ZT4 (STMicroelectronics): This cross-manufacturer substitute meets the core voltage rating (400 V) and package type (D2PAK) requirements. The continuous drain current is rated at 9 A compared to 10 A for the IRF740ASTRR, representing a 10% reduction in current capacity. On-state resistance remains at 550 mOhm but is specified at 4.5 A rather than 6 A. Gate charge is lower at 32 nC, and input capacitance is reduced to 930 pF. Power dissipation is rated at 110 W (Tc) versus 125 W (Tc). This part is suitable for applications where the 9 A current rating and reduced power dissipation are acceptable within circuit design margins. Both substitute parts are ROHS3 compliant and active in production status.

Frequently Asked Questions (FAQ)

Q: Can IRF740ASTRRPBF be used as a direct replacement for IRF740ASTRR?

A: Yes. IRF740ASTRRPBF is electrically and mechanically identical to IRF740ASTRR. The difference is packaging format: IRF740ASTRRPBF is supplied in Tape & Reel format while IRF740ASTRR is supplied in bulk. Both parts have identical electrical specifications and pinout. IRF740ASTRRPBF is the recommended substitute due to active product status and ROHS3 compliance.

Q: What are the limitations of STB11NK40ZT4 as a substitute?

A: STB11NK40ZT4 has a continuous drain current rating of 9 A compared to 10 A for the IRF740ASTRR. This represents a 10% reduction in maximum current capacity. Power dissipation is also reduced to 110 W (Tc) from 125 W (Tc). The on-state resistance specification point differs (4.5 A versus 6 A), though the maximum value remains 550 mOhm. These differences must be evaluated against circuit design margins and thermal requirements.

Q: Are all three parts pin-compatible?

A: Yes. All three parts use the TO-263 (D2PAK) package with identical pinout: 2 leads plus tab configuration. Physical footprint and mounting requirements are identical, allowing direct PCB substitution without layout modifications.

Q: What is the significance of the product status difference?

A: IRF740ASTRR is classified as obsolete, indicating it is no longer manufactured and existing inventory is limited. IRF740ASTRRPBF and STB11NK40ZT4 are both active products with ongoing production and availability. For new designs or long-term procurement, active products are preferred to ensure supply continuity.

Q: How do RoHS compliance differences affect substitution?

A: IRF740ASTRR is RoHS non-compliant, while both IRF740ASTRRPBF and STB11NK40ZT4 are ROHS3 compliant. For applications subject to RoHS regulations or customer requirements, the compliant substitutes are mandatory. For legacy systems without RoHS requirements, compliance status does not affect functional performance.

Q: What packaging options are available for each part?

A: IRF740ASTRR is supplied in bulk packaging. IRF740ASTRRPBF is supplied in Tape & Reel (TR) format. STB11NK40ZT4 is supplied in Cut Tape (CT) and Digi-Reel® format. Packaging selection depends on assembly process requirements and order quantities.

Q: Can STB11NK40ZT4 be used in high-current applications requiring the full 10 A rating?

A: STB11NK40ZT4 is rated for 9 A continuous drain current. Applications requiring sustained operation at 10 A should use IRF740ASTRRPBF to maintain the full current specification. For applications with peak currents below 9 A or with design margins accommodating the reduced rating, STB11NK40ZT4 is acceptable.