AOD425 MOSFET P-Channel 30V Equivalent & Substitute Parts

Part Overview

The AOD425 is a P-Channel MOSFET manufactured by Alpha & Omega Semiconductor Inc., rated for 30V drain-to-source voltage with continuous drain current of 9A at Ta and 50A at Tc in a Surface Mount TO-252 (DPAK) package. This device is classified as Obsolete, making identification of equivalent and substitute parts necessary for ongoing design support and procurement continuity. The AOD425 operates across a temperature range of -55°C to 175°C and is suitable for applications requiring P-Channel switching and linear regulation in compact surface mount form factors.

Substiute Parts

AOD425

Alpha & Omega Semiconductor Inc.In Stock: 10146AOD425 Datasheet

Current PartRFQ

FDD6685

onsemiIn Stock: 20485FDD6685 Datasheet

MFR RecommendedRFQ

NTD25P03LT4G

onsemiIn Stock: 32353NTD25P03LT4G Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AOD425 is determined by strict equivalence across the following critical parameters:

Mandatory Matching Criteria:

• FET Type: P-Channel
• Drain to Source Voltage (Vdss): 30V
• Package / Case: TO-252-3, DPAK (2 Leads + Tab), SC-63
• Mounting Type: Surface Mount
• Moisture Sensitivity Level: 1 (Unlimited)

Functional Compatibility Criteria:

• Continuous Drain Current (Ta or Tc): Must meet or exceed application requirements
• Rds On (Max): Lower or equivalent values indicate improved performance
• Vgs(th) (Max): Threshold voltage compatibility for gate drive circuits
• Gate Charge (Qg): Lower values reduce switching losses
• Input Capacitance (Ciss): Lower values improve switching speed
• Operating Temperature Range: Must encompass or exceed -55°C to 175°C
• Power Dissipation: Must support thermal requirements

The substitute parts FDD6685 and NTD25P03LT4G satisfy all mandatory matching criteria and provide functional equivalence within the specified electrical parameter ranges.

Parameter Comparison

Engineering Selection Recommendations

FDD6685 (onsemi PowerTrench®)

The FDD6685 is an Active product with ROHS3 compliance and REACH Unaffected status. It provides 11A continuous drain current at Ta and 40A at Tc, meeting or exceeding the AOD425 specifications for most applications. The FDD6685 exhibits lower gate charge (24 nC @ 5V versus 38 nC @ 10V) and reduced input capacitance (1715 pF @ 15V versus 2200 pF @ 15V), resulting in improved switching performance. The Rds On specification of 20 mOhm @ 11A, 10V is comparable to the AOD425 at 17 mOhm @ 20A, 10V. Operating temperature range matches the AOD425 at -55°C to 175°C. This device is suitable for direct substitution in applications where the Ta current rating of 11A is sufficient.

NTD25P03LT4G (onsemi)

The NTD25P03LT4G is an Active product with ROHS3 compliance and REACH Unaffected status. It provides 25A continuous drain current at Ta, significantly exceeding the AOD425 specification. The device exhibits the lowest gate charge (20 nC @ 5V) and input capacitance (1260 pF @ 25V) among the three options, enabling superior switching efficiency. However, the Rds On specification of 80 mOhm @ 25A, 5V is higher than the AOD425, and the maximum Vgs rating is ±15V compared to ±25V. The operating temperature range extends to -55°C to 150°C, which is 25°C lower than the AOD425 maximum. This device is suitable for applications requiring higher current capacity and improved switching characteristics, provided the thermal and gate voltage requirements are compatible.

Both substitute parts maintain identical package form factor (TO-252-3, DPAK), moisture sensitivity level (MSL 1), and regulatory compliance status (REACH Unaffected). Selection between FDD6685 and NTD25P03LT4G depends on specific application current requirements, thermal dissipation needs, and gate drive voltage constraints.

Frequently Asked Questions (FAQ)

Q: Can the FDD6685 be used as a direct replacement for the AOD425?

A: The FDD6685 is electrically and mechanically compatible with the AOD425. Both devices are P-Channel MOSFETs rated for 30V Vdss in TO-252-3 DPAK packages. The FDD6685 provides 11A continuous drain current at Ta, which meets or exceeds most applications requiring the AOD425. Verify that your specific application current requirements do not exceed 11A at Ta or 40A at Tc.

Q: What are the key differences between FDD6685 and NTD25P03LT4G?

A: The primary differences are continuous drain current (FDD6685: 11A Ta / 40A Tc; NTD25P03LT4G: 25A Ta), Rds On (FDD6685: 20 mOhm @ 11A, 10V; NTD25P03LT4G: 80 mOhm @ 25A, 5V), maximum Vgs rating (FDD6685: ±25V; NTD25P03LT4G: ±15V), and maximum operating temperature (FDD6685: 175°C; NTD25P03LT4G: 150°C). The NTD25P03LT4G offers higher current capacity and lower switching losses but higher on-resistance.

Q: Are both substitute parts available in the same packaging as the AOD425?

A: Yes. Both FDD6685 and NTD25P03LT4G are supplied in TO-252-3 DPAK (2 Leads + Tab) SC-63 packages, identical to the AOD425. No PCB layout modifications are required for substitution.

Q: What is the moisture sensitivity level for these devices?

A: All three devices—AOD425, FDD6685, and NTD25P03LT4G—carry MSL 1 (Unlimited) classification, indicating no moisture sensitivity restrictions during storage or handling.

Q: Are the substitute parts RoHS compliant?

A: The FDD6685 and NTD25P03LT4G are both ROHS3 Compliant. The AOD425 RoHS status is not specified in the provided data. Both substitute parts are REACH Unaffected, matching the AOD425 regulatory status.

Q: Which substitute part should I select for a high-temperature application?

A: The FDD6685 supports the full operating temperature range of -55°C to 175°C, matching the AOD425. The NTD25P03LT4G operates to -55°C to 150°C, which is 25°C lower at the maximum. For applications requiring operation above 150°C, the FDD6685 is the appropriate choice.

Q: How do gate charge specifications affect device selection?

A: Gate charge (Qg) determines the energy required to switch the device. The AOD425 requires 38 nC @ 10V, while FDD6685 requires 24 nC @ 5V and NTD25P03LT4G requires 20 nC @ 5V. Lower gate charge reduces switching losses and allows faster switching speeds. Both substitute parts offer improved gate charge performance.

Q: Can I use the NTD25P03LT4G in a circuit designed for the AOD425?

A: The NTD25P03LT4G is mechanically and electrically compatible but has three design considerations: (1) Maximum Vgs is ±15V versus ±25V for the AOD425, so gate drive circuits must not exceed ±15V; (2) Rds On is higher at 80 mOhm @ 25A, 5V, resulting in greater power dissipation; (3) Maximum operating temperature is 150°C versus 175°C. Verify these parameters against your circuit requirements before substitution.

Q: What inventory status should I consider when selecting a substitute?

A: The AOD425 is Obsolete with 10,073 pieces in stock. The FDD6685 is Active with 20,400 pieces in stock. The NTD25P03LT4G is Active with 32,273 pieces in stock. For long-term design continuity, Active products with higher inventory levels provide superior supply chain security.