SRP1055-4R3M Equivalent & Substitute Parts

Part Overview

The SRP1055-4R3M is a 4.3 µH shielded drum core wirewound inductor manufactured by Bourns Inc., rated for 10 A continuous current with a maximum DC resistance of 8.5 mOhm. This component is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and procurement continuity. Substitute parts must maintain the same inductance value, current rating capability, and shielding characteristics to ensure circuit performance and reliability.

Substiute Parts

SRP1055-4R3M

Bourns Inc.In Stock: 827SRP1055-4R3M Datasheet

Current PartRFQ

SCEP125U-4R3

Signal TransformerIn Stock: 973SCEP125U-4R3 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SRP1055-4R3M is determined by the following critical parameters:

Inductance Value: Substitute parts must provide 4.3 µH with ±20% tolerance to maintain circuit inductance specifications.

Current Rating: The substitute must support a minimum continuous current rating of 10 A to handle the design load without thermal degradation.

DC Resistance: The substitute DCR must not exceed 8.5 mOhm to prevent excessive power dissipation and thermal rise in the application.

Shielding: The substitute must be shielded to maintain electromagnetic compatibility and prevent coupling with adjacent circuit elements.

Mounting Type: Surface mount configuration is required for PCB assembly compatibility.

Compliance: RoHS3 compliance is mandatory for regulatory adherence in the target application.

The SCEP125U-4R3 from Signal Transformer meets these substitution criteria while offering improved current saturation performance and active product status.

Parameter Comparison

Engineering Selection Recommendations

The SCEP125U-4R3 is a qualified substitute for the obsolete SRP1055-4R3M based on the following factors:

Functional Equivalence: Both parts deliver 4.3 µH inductance with identical ±20% tolerance and shielded construction, ensuring equivalent circuit performance.

Current Capability: The SCEP125U-4R3 provides 10.5 A continuous current rating and 11 A saturation current, exceeding the SRP1055-4R3M requirements of 10 A and 8 A respectively.

Compliance Alignment: Both components maintain ROHS3 compliance and REACH unaffected status, satisfying regulatory requirements.

Product Availability: The SCEP125U-4R3 holds active product status with 882 pieces in stock, providing long-term procurement security compared to the obsolete SRP1055-4R3M.

Temperature Consideration: The SRP1055-4R3M operates across -55°C to 150°C, while the SCEP125U-4R3 operates across -40°C to 125°C. Applications requiring operation below -40°C or above 125°C must retain the original part or identify alternative solutions.

DCR Trade-off: The SCEP125U-4R3 exhibits 11.4 mOhm maximum DCR compared to 8.5 mOhm for the SRP1055-4R3M. This 34% increase in resistance results in proportionally higher power dissipation. Thermal analysis is required for applications with tight thermal budgets or continuous high-current operation.

Frequently Asked Questions (FAQ)

Q: Can the SCEP125U-4R3 directly replace the SRP1055-4R3M in all applications?

A: The SCEP125U-4R3 is functionally equivalent for inductance, current rating, and shielding. However, applications operating below -40°C or above 125°C require the original SRP1055-4R3M due to temperature range limitations. Additionally, circuits sensitive to inductor losses should evaluate the 3 mOhm DCR increase.

Q: What is the impact of the higher DC resistance in the SCEP125U-4R3?

A: The SCEP125U-4R3 DCR of 11.4 mOhm versus 8.5 mOhm increases resistive losses by approximately 34%. In a 10 A application, this translates to an additional 0.29 W of power dissipation. Thermal management and efficiency calculations should account for this difference.

Q: Are both parts surface mount compatible?

A: Yes, both the SRP1055-4R3M and SCEP125U-4R3 are surface mount inductors suitable for standard PCB assembly processes. Physical dimensions differ slightly (11.00mm x 9.35mm for SRP1055-4R3M versus 12.90mm x 12.90mm for SCEP125U-4R3), requiring footprint verification during layout.

Q: Do both parts meet current environmental and compliance standards?

A: Both components are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements for electronics manufacturing and distribution.

Q: Why is the SRP1055-4R3M classified as obsolete?

A: Obsolete status indicates the manufacturer has discontinued production. The SCEP125U-4R3 with active product status provides a viable path for design continuity and future procurement.