AO4405E P-Channel MOSFET Equivalent & Substitute Parts

Part Overview

The AO4405E is a P-Channel MOSFET manufactured by Alpha & Omega Semiconductor Inc., rated for 30V drain-to-source voltage with 6A continuous drain current at 25°C. The device is housed in an 8-SOIC surface mount package and is designed for general-purpose switching and amplification applications requiring P-channel enhancement-mode operation.

The AO4405E carries an Obsolete product status. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements for applications utilizing this component.

Substiute Parts

AO4405E

Alpha & Omega Semiconductor Inc.In Stock: 32878AO4405E Datasheet

Current PartRFQ

AOSP21311C

Alpha & Omega Semiconductor Inc.In Stock: 1140AOSP21311C Datasheet

MFR RecommendedRFQ

SI9435BDY-T1-E3

Vishay SiliconixIn Stock: 24358SI9435BDY-T1-E3 Datasheet

MFR RecommendedRFQ

SI9435BDY-T1-GE3

Vishay SiliconixIn Stock: 20272SI9435BDY-T1-GE3 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AO4405E is determined by electrical and mechanical compatibility across the following critical parameters:

Electrical Compatibility Criteria:

• Drain-to-source voltage rating (Vdss) must equal or exceed 30V
• Continuous drain current (Id) must meet or exceed 6A at 25°C
• On-resistance (Rds On) characteristics must support the application's power dissipation requirements
• Gate threshold voltage (Vgs(th)) must be compatible with the drive circuit
• Operating temperature range must encompass -55°C to 150°C
• FET type must remain P-Channel enhancement-mode

Mechanical Compatibility Criteria:

• Package type must be 8-SOIC surface mount
• Physical dimensions must match 0.154" × 3.90mm width specification
• Mounting type must be surface mount

Compliance Requirements:

• RoHS3 compliance required
• Moisture sensitivity level (MSL) of 1 (Unlimited) acceptable
• REACH unaffected status required

Substitute parts are grouped based on whether they maintain full electrical equivalence (matching or exceeding all electrical parameters) or represent functional alternatives with trade-offs in specific parameters such as current rating or on-resistance.

Parameter Comparison

Engineering Selection Recommendations

AOSP21311C (Alpha & Omega Semiconductor Inc.) — Primary Substitute

The AOSP21311C is the manufacturer-recommended substitute for the AO4405E. Both devices are manufactured by Alpha & Omega Semiconductor Inc. and share identical electrical ratings: 30V Vdss, 6A continuous drain current, and 2.5W power dissipation. The AOSP21311C exhibits superior on-resistance performance (42 mOhm versus 45 mOhm) and maintains full compatibility with the original design. The AOSP21311C carries Active product status, ensuring long-term availability and supply chain support. Both parts are ROHS3 compliant with MSL 1 (Unlimited) ratings. The primary difference is packaging format: AOSP21311C is supplied in Tape & Reel (TR) configuration, whereas the original AO4405E packaging format is not specified. This substitute is suitable for direct replacement in applications where the original 6A current rating and 2.5W power dissipation are required.

SI9435BDY-T1-E3 and SI9435BDY-T1-GE3 (Vishay Siliconix) — Functional Alternatives

The SI9435BDY-T1-E3 and SI9435BDY-T1-GE3 are functionally equivalent devices from Vishay Siliconix, both part of the TrenchFET® series. These devices maintain the 30V Vdss rating and 8-SOIC package compatibility. However, they are rated for 4.1A continuous drain current and 1.3W power dissipation, representing a reduction from the AO4405E's 6A and 2.5W specifications. The on-resistance remains equivalent at 42 mOhm. These devices are suitable for applications where the reduced current and power ratings are acceptable. Both variants carry Active product status and full ROHS3 compliance. The SI9435BDY-T1-E3 is supplied in Tape & Reel (TR) packaging, while the SI9435BDY-T1-GE3 is supplied in Cut Tape (CT) & Digi-Reel® format.

Selection Criteria Summary:

• For direct electrical equivalence with 6A current capability: select AOSP21311C
• For applications tolerating 4.1A current rating: select SI9435BDY-T1-E3 or SI9435BDY-T1-GE3 based on packaging requirements
• All substitutes maintain 30V Vdss, 8-SOIC package, -55°C to 150°C operating range, and ROHS3 compliance
• All substitutes carry Active product status, ensuring supply availability

Frequently Asked Questions (FAQ)

Q: Can the AOSP21311C directly replace the AO4405E in all applications?

A: The AOSP21311C is electrically equivalent to the AO4405E across all critical parameters: 30V Vdss, 6A continuous drain current, 2.5W power dissipation, and 8-SOIC package. Direct replacement is supported for applications designed around the AO4405E specifications. The AOSP21311C exhibits improved on-resistance (42 mOhm versus 45 mOhm), which provides a performance benefit.

Q: What are the limitations of the SI9435BDY-T1-E3 and SI9435BDY-T1-GE3 as substitutes?

A: The Vishay Siliconix devices are rated for 4.1A continuous drain current and 1.3W power dissipation, compared to the AO4405E's 6A and 2.5W ratings. These devices are suitable only for applications where the reduced current and power specifications are acceptable. The 30V Vdss rating, 8-SOIC package, and on-resistance characteristics remain compatible.

Q: Are there packaging differences between the substitute parts?

A: Yes. The AOSP21311C is supplied in Tape & Reel (TR) format. The SI9435BDY-T1-E3 is supplied in Tape & Reel (TR) format. The SI9435BDY-T1-GE3 is supplied in Cut Tape (CT) & Digi-Reel® format. All three maintain the 8-SOIC physical package specification. Packaging selection depends on assembly equipment and procurement requirements.

Q: Do all substitute parts meet RoHS and compliance requirements?

A: All substitute parts listed—AOSP21311C, SI9435BDY-T1-E3, and SI9435BDY-T1-GE3—are ROHS3 compliant, REACH unaffected, and carry MSL 1 (Unlimited) moisture sensitivity ratings. Compliance requirements are maintained across all substitutes.

Q: What is the difference between SI9435BDY-T1-E3 and SI9435BDY-T1-GE3?

A: Both devices are electrically identical Vishay Siliconix TrenchFET® MOSFETs with 30V Vdss, 4.1A continuous drain current, and 8-SOIC packaging. The primary difference is packaging format: SI9435BDY-T1-E3 uses Tape & Reel (TR) packaging, while SI9435BDY-T1-GE3 uses Cut Tape (CT) & Digi-Reel® packaging. Selection depends on assembly and procurement workflow requirements.

Q: Why is the AO4405E listed as Obsolete?

A: The AO4405E carries Obsolete product status, indicating that the manufacturer has discontinued active production and support. The AOSP21311C, manufactured by the same company (Alpha & Omega Semiconductor Inc.), is the recommended replacement with Active product status, ensuring continued availability and technical support.

Q: Can I use a substitute part with lower current rating in a design requiring 6A?

A: No. Applications requiring 6A continuous drain current must use parts rated for 6A or higher. The SI9435BDY-T1-E3 and SI9435BDY-T1-GE3, rated for 4.1A, are not suitable for such applications. The AOSP21311C, rated for 6A, is the appropriate substitute for designs requiring the full 6A current capability.

Q: Are gate charge and threshold voltage differences significant?

A: Gate charge and threshold voltage differences affect drive circuit design and switching characteristics. The AOSP21311C exhibits higher gate charge (23 nC versus 16 nC) and threshold voltage (2.2V versus 1.5V) compared to the AO4405E. The Vishay devices show further increases (24 nC and 3V respectively). These differences may require drive circuit adjustment but do not prevent substitution in applications with adequate gate drive capability.