SC312MF-330 Equivalent & Substitute Parts

Part Overview

The SC312MF-330 is a 33 µH shielded wirewound inductor manufactured by Signal Transformer, rated for 330 mA continuous current with a maximum DC resistance of 2.4 Ohm. This component is classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing design support and procurement continuity. The part operates across the industrial temperature range of -40°C to 125°C and is ROHS3 compliant.

Substiute Parts

SC312MF-330

Signal TransformerIn Stock: 762SC312MF-330 Datasheet

Current PartRFQ

74404041330

Würth ElektronikIn Stock: 1349374404041330 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SC312MF-330 is based on the following critical parameters:

• Inductance Value: 33 µH with ±20% tolerance
• Current Rating: Minimum 330 mA continuous current capability
• Shielding Configuration: Shielded construction required
• Mounting Technology: Surface mount package
• Operating Temperature: -40°C to 125°C range
• Compliance Standards: ROHS3 compliance maintained

The Würth Elektronik 74404041330 satisfies these substitution criteria with equivalent inductance, superior current rating (650 mA), lower DC resistance (628 mOhm), and active product status with AEC-Q200 qualification.

Parameter Comparison

Engineering Selection Recommendations

The 74404041330 from Würth Elektronik (WE-LQS series) is a direct functional substitute for the obsolete SC312MF-330. Both components maintain identical inductance specifications and operating temperature ranges. The substitute part provides enhanced performance characteristics: current rating increased from 330 mA to 650 mA, and DC resistance reduced from 2.4 Ohm to 628 mOhm, resulting in lower power dissipation and improved thermal performance.

The Würth Elektronik part carries active product status with AEC-Q200 automotive qualification, ensuring long-term availability and supply chain stability. Both components are ROHS3 compliant and maintain MSL 1 moisture sensitivity classification. The substitute is available in Tape & Reel packaging with significantly higher inventory levels (13,395 units in stock versus 723 units for the original part).

Frequently Asked Questions (FAQ)

Q: Can the 74404041330 be used as a direct replacement for SC312MF-330?

A: Yes. Both components share identical inductance values (33 µH ±20%), operating temperature ranges (-40°C to 125°C), shielding configuration, and surface mount technology. The substitute part exceeds the original specifications in current handling and reduces DC resistance, making it functionally compatible for applications designed around the SC312MF-330.

Q: What are the physical package differences between these parts?

A: The SC312MF-330 measures 0.150" L x 0.150" W (3.80mm x 3.80mm) with a seated height of 0.053" (1.35mm). The 74404041330 measures 0.157" L x 0.157" W (4.00mm x 4.00mm) with a seated height of 0.047" (1.20mm). Both are nonstandard surface mount packages. Physical layout verification is required for PCB footprint compatibility.

Q: Why is DC resistance significantly lower in the substitute part?

A: The 74404041330 exhibits 628 mOhm DC resistance compared to 2.4 Ohm in the SC312MF-330. This reduction reflects differences in wire gauge and core material optimization in the Würth Elektronik design, resulting in lower power dissipation and improved efficiency in the application circuit.

Q: Are both parts compliant with current regulatory standards?

A: Yes. Both the SC312MF-330 and 74404041330 are ROHS3 compliant, REACH unaffected, and classified under ECCN EAR99 with HTSUS code 8504.50.8000. The substitute part additionally carries AEC-Q200 automotive qualification.

Q: What is the saturation current difference between these inductors?

A: The SC312MF-330 saturates at 570 mA, while the 74404041330 saturates at 600 mA. Both values exceed their respective continuous current ratings, providing adequate margin for transient current conditions in typical applications.