SPD125R-333M Equivalent & Substitute Parts

Part Overview

The SPD125R-333M is a 33 µH shielded drum core wirewound inductor manufactured by API Delevan Inc., rated for 2.1 A continuous current with a maximum DC resistance of 95 mOhm. This surface mount component operates across the temperature range of -55°C to 125°C and is RoHS3 compliant. The part is currently active in production with 863 units in stock. Substitute parts are identified when equivalent inductance values, current ratings, and shielding characteristics align within acceptable tolerance and performance parameters, enabling design flexibility and supply chain continuity.

Substiute Parts

SPD125R-333M

API Delevan Inc.In Stock: 970SPD125R-333M Datasheet

Current PartRFQ

SRR1206-330YL

Bourns Inc.In Stock: 1305SRR1206-330YL Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SPD125R-333M is based on the following critical parameters:

Primary Substitution Criteria:

• Inductance value of 33 µH (matching nominal specification)
• Shielded drum core wirewound construction
• Ferrite core material
• Surface mount packaging
• RoHS3 compliance and MSL 1 rating

Secondary Compatibility Factors:

• Current rating of 1.9 A or higher (minimum acceptable for 2.1 A design requirement)
• DC resistance within acceptable range for power loss calculations
• Operating temperature range covering -55°C to 125°C or equivalent
• Nonstandard package case suitable for SMD assembly

The substitute part SRR1206-330YL from Bourns Inc. meets these criteria with equivalent inductance, shielding, and core construction, though with slightly reduced current rating and lower tolerance specification.

Parameter Comparison

Engineering Selection Recommendations

SPD125R-333M (Primary Part): The SPD125R-333M is the specified component with active production status and full inventory availability. It provides the highest current rating at 2.1 A and the widest operating temperature range (-55°C to 125°C). This part is suitable for applications requiring maximum thermal performance and current capacity within the 33 µH inductance class.

SRR1206-330YL (Substitute Part): The SRR1206-330YL is a qualified substitute when SPD125R-333M availability is constrained. This Bourns component maintains equivalent inductance, shielding, and core construction with RoHS3 compliance. The substitute exhibits lower DC resistance (90 mOhm vs. 95 mOhm) and tighter tolerance (±15% vs. ±20%), providing improved performance characteristics. However, the continuous current rating is reduced to 1.9 A, and the minimum operating temperature is -40°C instead of -55°C. Physical dimensions are slightly larger (12.70mm x 12.70mm vs. 12.00mm x 12.00mm) with increased height (6.50mm vs. 6.00mm). Both parts carry identical RoHS3 and MSL 1 certifications.

Selection between these parts depends on application current requirements, thermal environment, and available PCB space. For applications operating below -40°C or requiring sustained currents above 1.9 A, the SPD125R-333M is mandatory. For standard operating conditions within -40°C to 125°C and currents up to 1.9 A, the SRR1206-330YL provides a functionally equivalent alternative.

Frequently Asked Questions (FAQ)

Q: Can the SRR1206-330YL replace the SPD125R-333M in all applications?

A: The SRR1206-330YL is functionally equivalent for applications operating within -40°C to 125°C and requiring continuous currents up to 1.9 A. Applications requiring operation below -40°C or sustained currents above 1.9 A must use the SPD125R-333M.

Q: What is the difference in inductance tolerance between these parts?

A: The SPD125R-333M has ±20% tolerance, while the SRR1206-330YL has ±15% tolerance. The tighter tolerance of the substitute part provides improved inductance accuracy for precision circuit designs.

Q: Are there physical compatibility concerns when substituting?

A: Yes. The SRR1206-330YL is 0.70mm larger in length and width (12.70mm vs. 12.00mm) and 0.50mm taller (6.50mm vs. 6.00mm). PCB layout and component placement must accommodate these dimensional differences.

Q: Do both parts have identical compliance certifications?

A: Yes. Both the SPD125R-333M and SRR1206-330YL are RoHS3 compliant, REACH unaffected, and carry MSL 1 (unlimited moisture sensitivity level) ratings.

Q: What is the saturation current difference, and does it matter?

A: The SPD125R-333M has saturation current (Isat) of 2.1 A, while the SRR1206-330YL has 3.1 A. The higher saturation current of the substitute provides additional margin before inductance degradation occurs at elevated current levels.

Q: Which part has lower DC resistance?

A: The SRR1206-330YL has lower DC resistance at 90 mOhm maximum compared to 95 mOhm maximum for the SPD125R-333M. Lower resistance reduces power dissipation and heat generation in the inductor.