ELJ-QF4N3DF Equivalent & Substitute Parts

Part Overview

The ELJ-QF4N3DF is a 4.3 nH unshielded multilayer ceramic inductor manufactured by Panasonic Electronic Components in the 0402 (1005 Metric) surface mount package. This component is rated for 360 mA maximum current with 160mOhm DC resistance and operates across -40°C to 85°C. The product is currently obsolete, necessitating identification of functionally equivalent alternatives for ongoing design requirements and production continuity.

Substiute Parts

ELJ-QF4N3DF

Panasonic Electronic ComponentsIn Stock: 1050ELJ-QF4N3DF Datasheet

Current PartRFQ

MLG1005S4N3STD25

TDK CorporationIn Stock: 24842MLG1005S4N3STD25 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ELJ-QF4N3DF is based on the following critical parameters that must remain constant or compatible:

• Inductance Value: 4.3 nH with ±0.3nH tolerance
• Package / Case: 0402 (1005 Metric) surface mount
• Shielding Type: Unshielded
• Core Material: Ceramic
• Physical Dimensions: 0.039" L x 0.020" W (1.00mm x 0.50mm), Height 0.022" (0.55mm) max

The substitute part MLG1005S4N3STD25 from TDK Corporation meets these core requirements. While the substitute exhibits higher current rating (700 mA vs 360 mA) and lower DC resistance (200mOhm Max vs 160mOhm Max), these represent improved electrical performance characteristics that do not compromise compatibility in applications designed for the original part's specifications.

Parameter Comparison

Engineering Selection Recommendations

The MLG1005S4N3STD25 is a direct functional substitute for the obsolete ELJ-QF4N3DF. Selection is supported by the following factors:

• Identical Inductance and Tolerance: Both parts specify 4.3 nH ±0.3nH, ensuring equivalent circuit performance
• Package Compatibility: Identical 0402 (1005 Metric) surface mount package with matching physical dimensions enables direct PCB footprint compatibility
• Active Product Status: The TDK substitute is currently in active production with 24,769 pieces in stock, ensuring supply chain continuity
• Compliance Certifications: The substitute carries AEC-Q200 rating and ROHS3 compliance, meeting automotive and environmental standards
• Enhanced Specifications: Higher current rating (700 mA) and extended operating temperature range (-55°C ~ 125°C) provide design margin beyond the original part's specifications
• Moisture Sensitivity: Improved MSL rating (1 vs 2) indicates superior moisture handling characteristics

Frequently Asked Questions (FAQ)

Q: Can MLG1005S4N3STD25 be used as a direct replacement for ELJ-QF4N3DF?

A: Yes. Both inductors share identical inductance values (4.3 nH ±0.3nH), package type (0402 Metric), physical dimensions, and unshielded ceramic core construction. The substitute is electrically and mechanically compatible for direct PCB substitution.

Q: What are the differences between these two parts?

A: The primary differences are: (1) Current rating—MLG1005S4N3STD25 supports 700 mA versus 360 mA for ELJ-QF4N3DF; (2) DC resistance—200mOhm Max versus 160mOhm Max; (3) Operating temperature—-55°C to 125°C versus -40°C to 85°C; (4) Product status—Active versus Obsolete; (5) Packaging—Tape & Reel versus unspecified.

Q: Will the higher current rating of the substitute affect circuit performance?

A: No. Higher current rating indicates improved performance margin. The substitute will operate safely in applications designed for the original 360 mA specification without adverse effects.

Q: Are there any compliance or certification differences?

A: The substitute carries AEC-Q200 automotive qualification and ROHS3 compliance. The original part does not list these certifications. Both are REACH Unaffected and classified as EAR99.

Q: Is the 0402 package footprint identical between both parts?

A: Yes. Both parts use the 0402 (1005 Metric) surface mount package with identical dimensions: 0.039" L x 0.020" W (1.00mm x 0.50mm) and 0.022" (0.55mm) maximum seated height. No PCB layout modifications are required.

Q: What is the difference in self-resonant frequency?

A: The ELJ-QF4N3DF has a self-resonant frequency of 5GHz, while the MLG1005S4N3STD25 is 4.5GHz. This difference reflects manufacturing variations between manufacturers but does not affect substitution validity for the specified inductance value.