Würth Elektronik 744902039 Equivalent & Substitute Parts

Part Overview

The Würth Elektronik 744902039 is a 3.9 nH unshielded thin film inductor rated for 300 mA with a maximum DC resistance of 200mOhm, packaged in 0603 (1608 Metric) surface mount format. This component is classified as obsolete, necessitating identification of equivalent substitute parts for ongoing design requirements and procurement needs. Substitute parts must maintain the core electrical specifications while accommodating available packaging and performance variations.

Substiute Parts

744902039

Würth ElektronikIn Stock: 735744902039 Datasheet

Current PartRFQ

744901039

Würth ElektronikIn Stock: 130366744901039 Datasheet

DirectRFQ

L06033R9CGSTR

KYOCERA AVXIn Stock: 24244L06033R9CGSTR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 744902039 is determined by the following critical parameters:

Primary Matching Criteria:

• Inductance value: 3.9 nH (exact match required)
• Inductance tolerance: ±0.1nH or tighter
• Type: Thin film construction
• Shielding: Unshielded configuration
• RoHS compliance: ROHS3 Compliant

Secondary Compatibility Factors:

• Current rating: Equal to or greater than 300 mA
• DC resistance: Equal to or less than 200mOhm (lower DCR preferred for reduced losses)
• Operating temperature range: Minimum -40°C ~ 125°C coverage
• Mounting type: Surface mount
• Moisture sensitivity: MSL 1 (Unlimited)

Package Considerations: Substitutes may utilize alternative surface mount packages (0402, 0603) provided mechanical and thermal constraints of the application permit the dimensional variation. Package selection impacts board layout and thermal performance.

Parameter Comparison

Engineering Selection Recommendations

744901039 (Würth Elektronik WE-TCI Series): This substitute maintains identical inductance and tolerance specifications within the same manufacturer series. Current rating of 340 mA exceeds the original 300 mA requirement. However, DC resistance of 500mOhm is 2.5 times higher than the original specification, resulting in increased power dissipation. The 0402 package is physically smaller, which may present layout constraints or thermal management challenges in applications with tight board space or high-frequency operation. Product status is active with full availability.

L06033R9CGSTR (KYOCERA AVX Accu-L® Series): This substitute provides superior electrical performance with DC resistance of 120mOhm (40% lower than original), higher current rating of 500 mA, and improved Q factor of 25 at 450MHz. Package format matches the original 0603 (1608 Metric), eliminating layout redesign requirements. Inductance tolerance of ±0.2nH is wider than the original ±0.1nH specification. Extended operating temperature range of -55°C to 125°C provides additional thermal margin. Product status is active with substantial inventory availability. Non-magnetic core material is specified.

Both substitutes maintain ROHS3 compliance, MSL 1 rating, and unshielded thin film construction. Selection between substitutes depends on application-specific requirements regarding DC resistance, package footprint, and thermal performance.

Frequently Asked Questions (FAQ)

Q: Can 744901039 be used as a direct replacement for 744902039?

A: Electrical substitution is possible based on matching inductance value and tolerance. The 0402 package requires board layout modification. The significantly higher DC resistance (500mOhm vs 200mOhm) increases power loss and heat generation, which may impact circuit performance in applications sensitive to inductor losses.

Q: What are the advantages of L06033R9CGSTR over the original part?

A: L06033R9CGSTR offers lower DC resistance (120mOhm), higher current rating (500 mA), superior Q factor (25 @ 450MHz), and identical 0603 package format. These characteristics reduce power dissipation and maintain board layout compatibility. Extended temperature range provides additional operational margin.

Q: Does inductance tolerance affect substitution eligibility?

A: Inductance tolerance is a critical parameter. The original 744902039 specifies ±0.1nH tolerance. Both 744901039 (±0.1nH) and L06033R9CGSTR (±0.2nH) meet or approach this specification. Applications requiring tighter tolerance control should prioritize 744901039 or L06033R9CGSTR with ±0.1nH matching.

Q: Are package dimensions interchangeable between 0402 and 0603 formats?

A: No. 0402 (1.00mm x 0.50mm) and 0603 (1.60mm x 0.80mm) packages have different footprints and require separate PCB pad layouts. Height differences (0.40mm vs 0.55mm) may affect clearance in constrained assemblies. Package selection must align with board design specifications.

Q: What is the impact of DC resistance on circuit performance?

A: DC resistance causes I²R power loss in the inductor. Higher DCR increases heat generation and reduces circuit efficiency. Applications operating at high currents or requiring low-loss performance benefit from lower DCR values. L06033R9CGSTR with 120mOhm DCR provides superior performance compared to 744901039 with 500mOhm DCR.

Q: Are all substitutes RoHS compliant?

A: Yes. All three parts (744902039, 744901039, and L06033R9CGSTR) are ROHS3 compliant with MSL 1 (Unlimited) moisture sensitivity rating, meeting current environmental and reliability standards.