CDH74NP-680KC Equivalent & Substitute Parts

Part Overview

The CDH74NP-680KC is a 68 µH unshielded drum core wirewound inductor manufactured by Sumida America Components Inc. This surface mount component is rated for 1 A continuous current with a maximum DC resistance of 350 mOhm and operates across the temperature range of -40°C to 100°C. The part is currently active in production and ROHS3 compliant. Substitute parts are identified when equivalent inductance values, core materials, and mounting types are required but the original part becomes unavailable or inventory constraints necessitate alternative sourcing.

Substiute Parts

CDH74NP-680KC

Sumida America Components Inc.In Stock: 748CDH74NP-680KC Datasheet

Current PartRFQ

SDR7045-680K

Bourns Inc.In Stock: 2094SDR7045-680K Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the CDH74NP-680KC is permissible when the following core parameters remain constant or within acceptable engineering tolerances:

Critical Parameters for Substitution:

• Inductance value: 68 µH (±10% tolerance maintained)
• Core type: Drum core, wirewound ferrite construction
• Mounting type: Surface mount
• Shielding configuration: Unshielded
• Package format: Tape & Reel (TR)
• RoHS compliance: ROHS3 Compliant

Allowable Variation Parameters:

• Current rating: Substitute must support minimum 900 mA; higher ratings are acceptable
• DC resistance: Substitute must not exceed 350 mOhm maximum
• Operating temperature: Substitute range must encompass -40°C minimum; upper limit may extend beyond 100°C
• Physical dimensions: Minor variations acceptable within nonstandard package classification

The SDR7045-680K from Bourns Inc. meets all critical substitution criteria while providing enhanced performance characteristics in current saturation and thermal operating range.

Parameter Comparison

Engineering Selection Recommendations

Primary Consideration: Current Rating

The SDR7045-680K substitute is rated for 900 mA continuous current, compared to the CDH74NP-680KC at 1 A. Selection of the substitute is appropriate only when circuit design current requirements do not exceed 900 mA. For applications requiring the full 1 A rating of the original part, the CDH74NP-680KC must be retained.

Secondary Considerations:

Both parts maintain ROHS3 compliance and identical moisture sensitivity classification (MSL 1), ensuring equivalent environmental handling and regulatory status. The substitute offers improved DC resistance performance (280 mOhm versus 350 mOhm maximum), resulting in lower resistive losses and reduced heat generation under equivalent current loads.

The extended operating temperature range of the SDR7045-680K (-40°C to 125°C versus -40°C to 100°C) provides thermal margin for applications operating near the upper temperature boundary of the original specification.

Physical Footprint:

The SDR7045-680K occupies a smaller footprint (7.00mm x 7.00mm versus 8.00mm x 7.30mm) and lower profile (4.80mm versus 5.20mm seated height). PCB layout verification is required to confirm that the reduced dimensions do not conflict with existing component placement or clearance requirements.

Frequently Asked Questions (FAQ)

Q: Can the SDR7045-680K directly replace the CDH74NP-680KC in all applications?

A: Direct substitution is valid only for applications where the circuit current requirement does not exceed 900 mA. The original CDH74NP-680KC is rated for 1 A continuous current. If the design operates at currents between 900 mA and 1 A, the original part must be used to ensure compliance with current rating specifications.

Q: What is the significance of the lower DC resistance in the substitute part?

A: The SDR7045-680K exhibits a maximum DC resistance of 280 mOhm compared to 350 mOhm in the CDH74NP-680KC. Lower DC resistance reduces I²R losses during current flow, resulting in decreased heat dissipation and improved efficiency. This characteristic is beneficial in power-sensitive applications but does not affect substitution eligibility based on electrical function.

Q: Are there physical compatibility issues with the smaller footprint of the SDR7045-680K?

A: The substitute part is physically smaller in both length/width (7.00mm x 7.00mm versus 8.00mm x 7.30mm) and height (4.80mm versus 5.20mm). While the reduced dimensions generally facilitate PCB layout, verification of component placement, trace routing, and clearance to adjacent components is required before implementation.

Q: Do both parts share identical regulatory and environmental compliance?

A: Yes. Both the CDH74NP-680KC and SDR7045-680K are ROHS3 compliant and classified as Moisture Sensitivity Level 1 (unlimited). No additional environmental handling or regulatory considerations are introduced by substitution.

Q: What is the inductance frequency test difference between the two parts?

A: The CDH74NP-680KC inductance is specified at 1 kHz test frequency, while the SDR7045-680K is specified at 100 kHz. Both parts maintain the same 68 µH ±10% inductance value at their respective test frequencies. This difference reflects manufacturer measurement methodology and does not affect functional equivalence in circuit applications.

Q: Can the substitute part be used in applications requiring the full -40°C to 100°C temperature range?

A: Yes. The SDR7045-680K operating range of -40°C to 125°C encompasses the full -40°C to 100°C specification of the original part. The extended upper temperature limit of the substitute provides additional thermal margin without introducing compatibility issues.