AO4454 Equivalent & Substitute Parts

Part Overview

The AO4454 is an N-Channel MOSFET manufactured by Alpha & Omega Semiconductor Inc., rated for 100V drain-to-source voltage with 6.5A continuous drain current. The device is housed in an 8-SOIC surface mount package and is part of the SDMOS™ series. This part is currently classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement continuity.

Substiute Parts

AO4454

Alpha & Omega Semiconductor Inc.In Stock: 2363AO4454 Datasheet

Current PartRFQ

FDS3672

onsemiIn Stock: 108213FDS3672 Datasheet

MFR RecommendedRFQ

IRF7473TRPBF

Infineon TechnologiesIn Stock: 3919IRF7473TRPBF Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AO4454 is determined by strict electrical and mechanical compatibility across the following critical parameters:

Electrical Compatibility Criteria:

• Drain-to-Source Voltage (Vdss): Must equal or exceed 100V
• Continuous Drain Current (Id): Must meet or exceed 6.5A at 25°C
• On-State Resistance (Rds On): Must not exceed 36 mOhm at rated conditions
• Gate Threshold Voltage (Vgs(th)): Must be compatible with existing gate drive circuits
• Power Dissipation: Must support thermal requirements of the application
• Operating Temperature Range: Must span -55°C to 150°C

Mechanical Compatibility Criteria:

• Package Type: 8-SOIC surface mount package
• Pin Configuration: Identical 8-pin SOIC layout
• Physical Dimensions: 0.154" width, 3.90mm standard SOIC footprint

Both substitute parts (FDS3672 and IRF7473TRPBF) meet these criteria with equivalent or superior electrical performance and identical mechanical compatibility.

Parameter Comparison

Engineering Selection Recommendations

FDS3672 (onsemi PowerTrench®)

The FDS3672 is an active product with superior electrical performance relative to the obsolete AO4454. It provides 7.5A continuous drain current (15% higher than AO4454), reduced on-state resistance of 23 mOhm (36% improvement), and identical operating temperature range. The device is RoHS3 compliant and maintains REACH unaffected status. The FDS3672 is suitable for direct replacement in applications where the higher current rating and improved thermal characteristics provide design margin.

IRF7473TRPBF (Infineon HEXFET®)

The IRF7473TRPBF is an active product offering 6.9A continuous drain current (within 6% of AO4454 specification) and 26 mOhm on-state resistance. This device provides a closer electrical match to the original AO4454 specification while maintaining identical package compatibility and operating temperature range. The IRF7473TRPBF is RoHS3 compliant and REACH unaffected. This part is appropriate for applications requiring minimal design modification and electrical parameter alignment with the original specification.

Both substitute parts are active products with established supply chains, full compliance certifications, and identical 8-SOIC surface mount packaging. Selection between FDS3672 and IRF7473TRPBF depends on application-specific requirements for current capacity and on-state resistance performance.

Frequently Asked Questions (FAQ)

Q: Can the FDS3672 or IRF7473TRPBF be used as direct pin-for-pin replacements for the AO4454?

A: Yes. Both substitute parts use identical 8-SOIC surface mount packaging with matching pin configurations and physical dimensions (0.154" width, 3.90mm standard SOIC footprint). No PCB layout modifications are required.

Q: What are the key electrical differences between the AO4454 and its substitutes?

A: The FDS3672 provides higher continuous drain current (7.5A vs. 6.5A) and lower on-state resistance (23 mOhm vs. 36 mOhm). The IRF7473TRPBF offers 6.9A continuous current and 26 mOhm on-state resistance, providing closer alignment to the original AO4454 specification. Both maintain the same 100V drain-to-source voltage rating and -55°C to 150°C operating temperature range.

Q: Are there differences in gate drive requirements between these parts?

A: The AO4454 and FDS3672 share identical gate threshold voltage specifications (4V @ 250µA), while the IRF7473TRPBF has a higher threshold of 5.5V @ 250µA. Gate charge differs across all three parts: AO4454 (23 nC), FDS3672 (37 nC), and IRF7473TRPBF (61 nC). Existing gate drive circuits designed for the AO4454 may require evaluation for the IRF7473TRPBF due to higher gate charge.

Q: What is the significance of the higher input capacitance in the substitute parts?

A: The FDS3672 and IRF7473TRPBF exhibit higher input capacitance (2015 pF and 3180 pF respectively) compared to the AO4454 (1450 pF). This affects switching speed and gate drive power requirements. Applications with high-frequency switching or tight timing constraints should evaluate the impact of increased capacitance on circuit performance.

Q: Are both substitute parts compliant with current regulatory standards?

A: Yes. Both FDS3672 and IRF7473TRPBF are RoHS3 compliant, REACH unaffected, and classified as EAR99 for export control purposes. Both maintain MSL 1 (Unlimited) moisture sensitivity level, matching the AO4454 specification.

Q: Which substitute part should be selected for thermal-constrained applications?

A: The FDS3672 offers superior thermal performance with 2.5W maximum power dissipation compared to the AO4454's 3.1W rating, combined with lower on-state resistance. This makes the FDS3672 preferable for applications where thermal management is critical. The IRF7473TRPBF also provides 2.5W maximum power dissipation.

Q: What is the current availability status of these substitute parts?

A: The AO4454 is obsolete with 2352 pieces in stock. The FDS3672 is active with 108,190 pieces available. The IRF7473TRPBF is active with 3,870 pieces available. Both substitute parts have established supply chains through active product lines.