ELF-18D270B Common Mode Choke Equivalent & Substitute Parts

Part Overview

The ELF-18D270B is a 2-line common mode choke manufactured by Panasonic Electronic Components, designed for through-hole mounting applications requiring 400mA current handling capability. This component features a typical DC resistance of 1.707Ohm and is housed in a vertical 4-pin package with dimensions of 20.00mm × 21.00mm × 20.00mm (L × W × H).

The ELF-18D270B is classified as obsolete. Locating equivalent substitute parts is necessary to maintain design continuity and ensure component availability for new production runs, repairs, and system upgrades.

Substiute Parts

ELF-18D270B

Panasonic Electronic ComponentsIn Stock: 744ELF-18D270B Datasheet

Current PartRFQ

7448640404

Würth ElektronikIn Stock: 16217448640404 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the ELF-18D270B are identified based on the following critical parameters that determine functional equivalence:

• Number of Lines: Must be 2-line configuration
• Current Rating (Max): Must support minimum 400mA
• Mounting Type: Must be through-hole compatible
• Package / Case: Must be vertical 4-pin configuration
• DC Resistance (Typ): Must be within acceptable range (1.61Ohm to 1.707Ohm)

The Würth Elektronik part 7448640404 meets these substitution criteria. It maintains the same 2-line, 400mA, through-hole vertical 4-pin architecture with comparable DC resistance of 1.61Ohm (Typ), making it functionally equivalent for the same application space.

Parameter Comparison

Engineering Selection Recommendations

The Würth Elektronik 7448640404 is the qualified substitute for the obsolete ELF-18D270B based on the following engineering factors:

Functional Equivalence: Both parts maintain identical 2-line, 400mA through-hole configurations with comparable DC resistance values (1.61Ohm vs. 1.707Ohm), ensuring electrical performance parity in common mode choke applications.

Product Status: The 7448640404 is classified as active, providing assured long-term availability and supply chain continuity compared to the obsolete ELF-18D270B.

Compliance Advantage: The 7448640404 is ROHS3 compliant, whereas the ELF-18D270B is RoHS non-compliant. This compliance status is significant for applications subject to RoHS regulations and modern procurement standards.

Physical Compatibility: The substitute part exhibits a slightly smaller height profile (17.80mm vs. 20.00mm), which may provide layout advantages in space-constrained applications. Footprint dimensions are comparable (21.20mm vs. 20.00mm/21.00mm), supporting direct board-level substitution.

Specified Operating Parameters: The 7448640404 provides documented AC voltage rating (250V) and operating temperature range (-40°C ~ 125°C), offering greater specification transparency than the original part.

Frequently Asked Questions (FAQ)

Q: Can the Würth Elektronik 7448640404 be used as a direct replacement for the ELF-18D270B?

A: Yes. Both parts share identical electrical specifications for the critical parameters: 2-line configuration, 400mA current rating, and comparable DC resistance (1.61Ohm vs. 1.707Ohm). The through-hole vertical 4-pin package architecture is identical, supporting direct board-level substitution.

Q: What are the key differences between these two parts?

A: The primary differences are product status (active vs. obsolete), RoHS compliance (ROHS3 vs. non-compliant), and physical dimensions. The 7448640404 is 2.2mm shorter in height and has slightly larger footprint dimensions. The substitute part also provides specified AC voltage rating and operating temperature range.

Q: Are there any PCB layout considerations when substituting the 7448640404 for the ELF-18D270B?

A: The footprint is compatible for direct substitution. The 7448640404 is 2.2mm shorter in height, which may require verification if the original design has height-critical constraints. Horizontal dimensions are comparable and support standard through-hole mounting practices.

Q: Does the lower DC resistance of the 7448640404 (1.61Ohm vs. 1.707Ohm) affect circuit performance?

A: The 1.61Ohm DC resistance of the 7448640404 is lower than the 1.707Ohm of the ELF-18D270B, resulting in reduced power dissipation and improved efficiency. This represents a performance improvement for the application.

Q: What is the significance of the RoHS compliance difference?

A: The ELF-18D270B is RoHS non-compliant, while the 7448640404 is ROHS3 compliant. For applications subject to RoHS regulations or modern procurement requirements, the 7448640404 is the appropriate choice.

Q: Is the 250V AC voltage rating of the 7448640404 relevant for substitution?

A: The 250V AC rating of the 7448640404 provides documented voltage handling capability. If the original application operates within this voltage specification, the substitute part is suitable. Verify that your application voltage requirements do not exceed this rating.