ELJ-SA121KF Equivalent & Substitute Parts

Part Overview

The ELJ-SA121KF is a 120 µH shielded inductor manufactured by Panasonic Electronic Components, designed for surface mount applications in the 1210 (3225 Metric) package. This component is rated for 5 mA maximum current with 8Ohm maximum DC resistance and operates at a self-resonant frequency of 9 MHz. The part is currently obsolete, making equivalent substitutes necessary for ongoing production and maintenance applications.

Substiute Parts

ELJ-SA121KF

Panasonic Electronic ComponentsIn Stock: 1128ELJ-SA121KF Datasheet

Current PartRFQ

SP1210R-124K

API Delevan Inc.In Stock: 779SP1210R-124K Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the ELJ-SA121KF is determined by the following critical parameters:

• Inductance Value: 120 µH (±10% tolerance maintained)
• Package / Case: 1210 (3225 Metric) surface mount form factor
• Shielding: Shielded construction required
• Physical Compatibility: Dimensions and height must accommodate existing PCB layouts

The SP1210R-124K from API Delevan Inc. qualifies as a functional substitute based on matching inductance value, package type, shielding specification, and surface mount configuration. While the substitute exhibits different current ratings and DC resistance characteristics, these parameters remain within acceptable ranges for applications where the ELJ-SA121KF was originally specified.

Parameter Comparison

Engineering Selection Recommendations

The SP1210R-124K is an active production substitute for the obsolete ELJ-SA121KF. Selection should be based on the following factors:

• Product Availability: The SP1210R-124K is currently in active production with 712 units in stock, whereas the ELJ-SA121KF is obsolete with limited remaining inventory.
• Compliance Status: The SP1210R-124K meets ROHS3 compliance and REACH unaffected status, ensuring regulatory alignment for new designs and production runs.
• Physical Fit: Dimensional differences are minimal (0.002" length variance, 0.007" height variance), compatible with standard 1210 footprints.
• Electrical Performance: The substitute provides superior current handling (147 mA vs. 5 mA) with marginally higher DC resistance (9.6Ohm vs. 8Ohm), suitable for applications where the original part was specified.

Frequently Asked Questions (FAQ)

Q: Can the SP1210R-124K directly replace the ELJ-SA121KF in existing designs?

A: Yes. Both components share identical inductance values (120 µH), tolerance (±10%), shielding type, and 1210 package footprint. Physical dimensions are within standard PCB layout tolerances.

Q: What are the key differences between these parts?

A: The SP1210R-124K has a higher current rating (147 mA vs. 5 mA) and slightly higher DC resistance (9.6Ohm vs. 8Ohm). The substitute uses a drum core, wirewound construction with ferrite core material. Operating temperature range is specified for the substitute (-55°C ~ 125°C) but not provided for the original part.

Q: Are there any height clearance concerns?

A: The SP1210R-124K has a maximum seated height of 0.101" (2.57mm) compared to 0.094" (2.40mm) for the ELJ-SA121KF. This 0.007" difference is within standard PCB design margins for 1210 components and should not cause clearance issues in typical applications.

Q: What is the inductance frequency test condition for each part?

A: The ELJ-SA121KF inductance is tested at 1 MHz, while the SP1210R-124K is tested at 100 kHz. Both maintain the specified 120 µH inductance value within their respective test conditions.

Q: Is the SP1210R-124K suitable for high-frequency applications?

A: The ELJ-SA121KF specifies a self-resonant frequency of 9 MHz. The SP1210R-124K does not provide this specification in the available data. Application suitability depends on specific frequency requirements and should be evaluated against circuit operating conditions.