SPD125R-334M Equivalent & Substitute Parts Reference

Part Overview

The SPD125R-334M is a 330 µH shielded drum core wirewound inductor manufactured by API Delevan Inc., rated for 700 mA continuous current with a maximum DC resistance of 600mOhm. The component is surface mount packaged in a nonstandard 12.00mm × 12.00mm form factor with a seated height of 6.00mm. The part is currently active in production and ROHS3 compliant. Substitute parts are necessary to accommodate supply chain availability, performance variations, and design optimization requirements where higher current ratings, lower DC resistance, or alternative compliance certifications provide operational advantages.

Substiute Parts

SPD125R-334M

API Delevan Inc.In Stock: 1055SPD125R-334M Datasheet

Current PartRFQ

744771233

Würth ElektronikIn Stock: 10523744771233 Datasheet

SimilarRFQ

SLF12565T-331MR87-H

TDK CorporationIn Stock: 1306SLF12565T-331MR87-H Datasheet

SimilarRFQ

SRR1206-331KL

Bourns Inc.In Stock: 1247SRR1206-331KL Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SPD125R-334M is determined by the following critical parameters: identical inductance value (330 µH), compatible inductance tolerance (±20% or tighter), current rating greater than or equal to 700 mA, DC resistance within acceptable limits for the application, ferrite core material, shielded construction, surface mount packaging, and compliance with ROHS3 requirements.

The three substitute parts listed below meet the inductance and core material requirements. Acceptable substitutes must maintain the 330 µH nominal value, support surface mount assembly, provide shielding equivalent to the original design, and operate within the specified temperature range. DC resistance and saturation current variations are permissible provided the substitute's continuous current rating meets or exceeds 700 mA.

Parameter Comparison

Engineering Selection Recommendations

The SPD125R-334M remains the primary component choice for new designs with active production status and ROHS3 compliance.

The Würth Elektronik 744771233 offers a direct mechanical footprint match (12.00mm × 12.00mm × 6.00mm) with improved electrical performance: higher continuous current rating (780 mA versus 700 mA) and lower DC resistance (510 mOhm versus 600 mOhm). This part includes AEC-Q200 automotive-grade qualification. Dimensional compatibility and superior DC characteristics make this an optimal substitute when supply of the original part is unavailable.

The Bourns SRR1206-331KL meets the minimum current requirement (600 mA) with tighter inductance tolerance (±10% versus ±20%), though it exhibits slightly higher DC resistance (660 mOhm). The part is active in production with ROHS3 compliance. Dimensional differences (12.70mm × 12.70mm × 6.50mm) require layout verification before implementation.

The TDK SLF12565T-331MR87-H is designated "Not For New Designs" and therefore is not recommended for future development. Dimensional variations (12.50mm × 12.50mm × 6.85mm) introduce additional layout constraints. This part is retained in this reference for legacy design compatibility only.

Frequently Asked Questions (FAQ)

Q: Can I use the Würth Elektronik 744771233 as a direct replacement for the SPD125R-334M?

A: Yes. The 744771233 shares identical inductance (330 µH), tolerance (±20%), core material (ferrite), shielding, mounting type (surface mount), and physical footprint (12.00mm × 12.00mm × 6.00mm). The higher current rating (780 mA) and lower DC resistance (510 mOhm) make it electrically compatible and functionally superior for the same application.

Q: What are the dimensional constraints when considering the Bourns SRR1206-331KL?

A: The Bourns part measures 12.70mm × 12.70mm with a seated height of 6.50mm, compared to the original SPD125R-334M at 12.00mm × 12.00mm × 6.00mm. Layout verification is required to ensure adequate clearance in the PCB design and no interference with adjacent components.

Q: Why is the TDK SLF12565T-331MR87-H marked "Not For New Designs"?

A: This designation indicates that TDK has transitioned this part to end-of-life status and does not recommend its use in new product development. While functionally compatible, new designs should utilize the SPD125R-334M or the Würth Elektronik 744771233 to ensure long-term supply chain availability and manufacturability.

Q: What is the significance of the Bourns part having ±10% tolerance compared to ±20%?

A: Tighter tolerance provides greater inductance accuracy, which may be advantageous in applications with strict inductance specifications. However, both tolerance levels (±10% and ±20%) are interchangeable from a functional standpoint if the application design permits ±20% variation.

Q: Are there temperature range differences between substitute parts?

A: The SPD125R-334M operates from -55°C to 125°C, while all three substitute parts operate from -40°C to 125°C. Applications requiring full -55°C operation must use the original SPD125R-334M or confirm that the -40°C lower limit is acceptable for the end system.