AX02-303R9 Equivalent & Substitute Parts

Part Overview

The AX02-303R9 is a 3.9 µH shielded drum core wirewound inductor manufactured by Triad Magnetics, rated for 10 A continuous current with a maximum DC resistance of 6.8 mOhm. This surface mount component is designed for applications requiring compact, high-current inductive filtering and energy storage in power conversion circuits. The part is currently active in production with full RoHS3 compliance. Substitute parts are identified when equivalent electrical performance can be achieved within the specified parameter tolerances while maintaining functional compatibility in the target application.

Substiute Parts

AX02-303R9

Triad MagneticsIn Stock: 1028AX02-303R9 Datasheet

Current PartRFQ

SRP1250-3R3M

Bourns Inc.In Stock: 3863SRP1250-3R3M Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AX02-303R9 is evaluated based on the following critical parameters:

Inductance Value: The substitute part must fall within the ±20% tolerance band of 3.9 µH, establishing an acceptable range of 3.12 µH to 4.68 µH.

Current Rating: The substitute must support the continuous current requirement of the application. Parts with equal or higher current ratings are acceptable.

DC Resistance (DCR): Lower DCR values reduce power dissipation and heat generation. The substitute DCR must not significantly exceed the 6.8 mOhm specification to maintain thermal performance.

Core Material and Shielding: Both the main part and substitute utilize shielded drum core construction, which is mandatory for EMI containment in compact surface mount applications.

Mounting Type: Both parts are surface mount components compatible with standard PCB assembly processes.

Compliance: RoHS3 compliance is required for all substitute parts to meet regulatory requirements.

The SRP1250-3R3M by Bourns Inc. is identified as a substitute based on its inductance value of 3.3 µH, which falls within the acceptable tolerance range, combined with its higher current rating and active product status.

Parameter Comparison

Engineering Selection Recommendations

Primary Part (AX02-303R9): Recommended for applications where ferrite core characteristics, compact J-lead package geometry, and the specified -40°C to 85°C operating range are design requirements. Active product status and full inventory availability support production continuity.

Substitute Part (SRP1250-3R3M): Acceptable as an alternative when the following conditions are met:

1. The application current requirement does not exceed 15 A continuous rating.
2. The inductance tolerance of ±20% accommodates the 3.3 µH value within circuit performance specifications.
3. The increased DC resistance of 9.2 mOhm does not create unacceptable thermal dissipation in the target application.
4. The iron core material is compatible with the circuit's frequency response and EMI requirements.
5. The nonstandard package dimensions can be accommodated within PCB layout constraints.
6. The extended operating temperature range (-55°C to 150°C) meets or exceeds application requirements.

Both parts maintain RoHS3 compliance and REACH unaffected status, satisfying regulatory requirements for commercial and industrial applications.

Frequently Asked Questions (FAQ)

Q: Can the SRP1250-3R3M directly replace the AX02-303R9 without circuit modification?

A: Direct replacement requires verification of three factors: (1) the 3.3 µH inductance value must satisfy the circuit's ±20% tolerance specification; (2) the increased DCR of 9.2 mOhm versus 6.8 mOhm must not cause excessive heat dissipation; (3) the nonstandard package dimensions must fit the PCB footprint. Physical layout verification is mandatory before implementation.

Q: What is the significance of the different core materials (ferrite vs. iron)?

A: Ferrite cores (AX02-303R9) typically exhibit lower losses at higher frequencies and better EMI shielding characteristics. Iron cores (SRP1250-3R3M) provide higher saturation current and better performance at lower frequencies. Core material selection depends on the circuit's operating frequency and current profile. Verify frequency response requirements before substitution.

Q: Why is the DC resistance higher in the substitute part?

A: The SRP1250-3R3M exhibits 9.2 mOhm maximum DCR compared to 6.8 mOhm for the AX02-303R9. This difference results from core material and winding design variations. Higher DCR increases resistive losses and heat generation. Calculate power dissipation (P = I²R) at maximum operating current to confirm thermal compatibility with the application's thermal management design.

Q: Are both parts suitable for the same temperature range applications?

A: The AX02-303R9 operates from -40°C to 85°C, while the SRP1250-3R3M operates from -55°C to 150°C. The substitute part supports a wider temperature range. If the application requires operation below -40°C or above 85°C, only the SRP1250-3R3M is suitable. For applications within -40°C to 85°C, both parts are acceptable.

Q: What packaging differences exist between these parts?

A: The AX02-303R9 uses a standard 2-SMD J-Lead package (13.30mm L × 15.00mm W × 6.50mm H). The SRP1250-3R3M uses a nonstandard package (13.90mm L × 13.50mm W × 5.90mm H). Footprint compatibility must be verified through dimensional comparison and PCB layout simulation before design implementation.

Q: Are both parts RoHS3 compliant?

A: Yes, both the AX02-303R9 and SRP1250-3R3M are RoHS3 compliant and REACH unaffected, meeting regulatory requirements for commercial and industrial applications in regulated markets.