LK2125R68K-T Equivalent & Substitute Parts

Part Overview

The LK2125R68K-T is a 680 nH shielded multilayer inductor manufactured by Taiyo Yuden, rated for 150 mA maximum current with a maximum DC resistance of 600mOhm. This component is packaged in the 0805 (2012 Metric) surface mount form factor and operates across the temperature range of -40°C to 85°C. The part is classified as obsolete, necessitating identification of active equivalent components that maintain electrical and mechanical compatibility for ongoing production and repair applications.

Substiute Parts

LK2125R68K-T

Taiyo YudenIn Stock: 1071LK2125R68K-T Datasheet

Current PartRFQ

CV201210-R68K

Bourns Inc.In Stock: 2757CV201210-R68K Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LK2125R68K-T is determined by strict equivalence across the following critical parameters:

Electrical Parameters:

• Inductance value: 680 nH with ±10% tolerance
• Current rating: 150 mA minimum
• DC resistance: Must not exceed 600mOhm maximum
• Quality factor: 25 @ 25MHz
• Self-resonant frequency: 105 MHz

Mechanical Parameters:

• Package type: 0805 (2012 Metric) surface mount
• Physical dimensions: 0.079" L × 0.049" W (2.00mm × 1.25mm)
• Maximum seated height: 0.057" (1.45mm)
• Shielding: Shielded construction required

Environmental & Compliance Parameters:

• Operating temperature range: -40°C to 85°C minimum
• RoHS3 compliance required
• Moisture sensitivity level: 1 (Unlimited)

The CV201210-R68K from Bourns Inc. qualifies as a direct substitute based on matching inductance, current rating, package dimensions, shielding type, and compliance certifications. The substitute part operates across an extended temperature range (-55°C to 125°C) and maintains equivalent electrical performance at the specified test frequency.

Parameter Comparison

Engineering Selection Recommendations

The CV201210-R68K from Bourns Inc. is the qualified substitute for the obsolete LK2125R68K-T. Selection of this substitute is based on the following engineering criteria:

Electrical Compatibility: The substitute part maintains identical inductance value (680 nH), tolerance (±10%), current rating (150 mA), quality factor (25 @ 25MHz), and self-resonant frequency (105 MHz). The DC resistance of the substitute (800 mOhm maximum) exceeds the original specification (600 mOhm maximum), which represents a degradation in this parameter. Applications sensitive to DC resistance performance must evaluate whether this increase is acceptable for the intended circuit function.

Mechanical Compatibility: Both components share identical package dimensions (0805 / 2012 Metric), physical footprint (0.079" L × 0.049" W), and maximum seated height (0.057"). Direct board-level substitution is mechanically feasible without PCB redesign.

Environmental & Compliance: The substitute part maintains ROHS3 compliance and MSL 1 (Unlimited) rating, ensuring regulatory and manufacturing process compatibility. The extended operating temperature range (-55°C to 125°C) of the substitute exceeds the original specification (-40°C to 85°C), providing enhanced thermal margin for applications operating at temperature extremes.

Product Status: The CV201210-R68K is classified as active with confirmed inventory availability (2711 pieces), ensuring long-term supply continuity compared to the obsolete LK2125R68K-T.

Frequently Asked Questions (FAQ)

Q: Can the CV201210-R68K directly replace the LK2125R68K-T on existing PCBs?

A: Yes. Both components share identical 0805 (2012 Metric) package dimensions and surface mount footprints. No PCB layout modifications are required for mechanical substitution.

Q: What is the significance of the DC resistance difference (600 mOhm vs. 800 mOhm)?

A: The substitute part has a maximum DC resistance 200 mOhm higher than the original. In circuits where inductor DC resistance directly affects performance (such as low-noise amplifier input matching networks or high-current power distribution), this difference may impact impedance matching, insertion loss, or thermal dissipation. Circuit-level analysis is necessary to determine acceptability.

Q: Are both parts RoHS compliant?

A: Yes. Both the LK2125R68K-T and CV201210-R68K are ROHS3 compliant and carry MSL 1 (Unlimited) moisture sensitivity ratings, meeting current environmental and manufacturing standards.

Q: Does the extended temperature range of the substitute part affect compatibility?

A: No. The substitute's operating range (-55°C to 125°C) encompasses the original specification (-40°C to 85°C). Extended temperature capability does not introduce incompatibility; it provides additional thermal margin for applications operating outside the original temperature window.

Q: What is the inductance tolerance for both parts?

A: Both components are specified with ±10% inductance tolerance at the 25 MHz test frequency. This tolerance applies equally to both the original and substitute parts.

Q: Are there packaging format differences between these parts?

A: The LK2125R68K-T is supplied in standard packaging, while the CV201210-R68K is available in Cut Tape (CT) and Digi-Reel® formats. Both formats are compatible with standard surface mount assembly processes.

Q: What is the quality factor specification for these inductors?

A: Both parts are specified with a quality factor (Q) of 25 measured at 25 MHz, indicating equivalent high-frequency performance characteristics.

Q: Is the self-resonant frequency identical between both parts?

A: Yes. Both the LK2125R68K-T and CV201210-R68K have a self-resonant frequency of 105 MHz, ensuring equivalent behavior at frequencies approaching the resonant point.