Würth Elektronik 7440430039 Equivalent & Substitute Parts

Part Overview

The Würth Elektronik 7440430039 is a 3.9 µH shielded drum core wirewound inductor rated for 1.72 A with a maximum DC resistance of 60mOhm. This surface mount component operates across the temperature range of -40°C to 125°C and is packaged in the 1919 (4848 Metric) form factor. The part is currently active in production with ROHS3 compliance and unlimited moisture sensitivity rating. Substitute parts are identified when equivalent electrical and mechanical specifications are required due to inventory constraints, supply chain considerations, or design flexibility needs.

Substiute Parts

7440430039

Würth ElektronikIn Stock: 22597440430039 Datasheet

Current PartRFQ

SRR4028-3R9Y

Bourns Inc.In Stock: 2732SRR4028-3R9Y Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the Würth Elektronik 7440430039 is determined by strict equivalence across the following critical parameters:

Inductance value of 3.9 µH with ±30% tolerance ensures functional compatibility in the target circuit application. Current rating of 1.72 A establishes the maximum continuous current capacity. DC resistance of 60mOhm maximum defines the resistive losses in the inductor. The 1919 (4848 Metric) package and surface mount configuration ensure mechanical and assembly compatibility. Operating temperature range of -40°C to 125°C and self-resonant frequency of 55 MHz establish the operational envelope. Ferrite shielded drum core construction with wirewound design provides the electromagnetic performance profile.

The Bourns Inc. SRR4028-3R9Y meets all these critical parameters and qualifies as a direct substitute.

Parameter Comparison

Engineering Selection Recommendations

Both the Würth Elektronik 7440430039 and Bourns Inc. SRR4028-3R9Y are active production components with identical ROHS3 compliance and REACH unaffected status. Both components carry EAR99 export classification and unlimited moisture sensitivity rating. The self-resonant frequency differential of 1 MHz (55 MHz versus 56 MHz) falls within acceptable engineering tolerance for applications operating at the specified 100 kHz test frequency. Selection between these parts may be based on availability, supply chain logistics, or design documentation requirements, as electrical and mechanical performance are equivalent.

Frequently Asked Questions (FAQ)

Q: Can the Bourns Inc. SRR4028-3R9Y be used as a direct replacement for the Würth Elektronik 7440430039?

A: Yes. Both components share identical inductance values, current ratings, DC resistance specifications, package dimensions, and operating temperature ranges. The 1 MHz difference in self-resonant frequency does not affect substitutability for applications specified at 100 kHz.

Q: Are there any compliance or certification differences between these parts?

A: No. Both parts are ROHS3 compliant, REACH unaffected, and carry EAR99 export classification. Both have unlimited moisture sensitivity rating (MSL 1).

Q: What are the key parameters that determine substitutability for this inductor?

A: Inductance value (3.9 µH), inductance tolerance (±30%), current rating (1.72 A), DC resistance (60mOhm maximum), package type (1919 / 4848 Metric), and operating temperature range (-40°C to 125°C) are the critical parameters that establish substitution eligibility.

Q: Do these parts have identical physical dimensions?

A: Yes. Both components measure 0.189" L x 0.189" W (4.80mm x 4.80mm) with a maximum seated height of 0.118" (3.00mm). They are compatible with identical PCB footprints and assembly processes.

Q: What is the difference in saturation current between these parts?

A: The Würth Elektronik 7440430039 has a saturation current (Isat) of 1.65A, while the Bourns Inc. SRR4028-3R9Y has an Isat of 1.5A. Both values exceed the rated current of 1.72A, ensuring adequate performance margin in the specified operating range.