SPD73R-124M Equivalent & Substitute Parts

Part Overview

The SPD73R-124M is a 120 µH shielded drum core wirewound inductor manufactured by API Delevan Inc., designed for surface mount applications with a current rating of 800 mA and maximum DC resistance of 840 mOhm. This component is classified as Active product status and is RoHS3 compliant. Substitute parts are identified when equivalent inductance values, compatible current ratings, and matching package dimensions are available from alternative manufacturers, enabling procurement flexibility and supply chain continuity.

Substiute Parts

SPD73R-124M

API Delevan Inc.In Stock: 1067SPD73R-124M Datasheet

Current PartRFQ

SRR0745A-121M

Bourns Inc.In Stock: 3971SRR0745A-121M Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SPD73R-124M are identified based on the following critical parameters:

Inductance Value: 120 µH with ±20% tolerance is the primary functional requirement. Substitute parts must match this inductance specification.

Current Rating and Saturation Current: The SPD73R-124M is rated for 800 mA continuous current with 800 mA saturation current. Substitute parts with equal or higher current ratings are acceptable for direct replacement.

DC Resistance (DCR): Maximum DCR of 840 mOhm defines the resistive losses. Substitute parts with equal or lower DCR values maintain or improve performance characteristics.

Package Dimensions: Surface mount package with 7.30 mm × 7.30 mm footprint and 3.90 mm maximum seated height must be maintained for mechanical compatibility.

Shielding and Core Material: Ferrite core with shielding is required to maintain electromagnetic performance and noise isolation properties.

Compliance and Environmental Ratings: RoHS3 compliance, MSL Level 1, and operating temperature range are mandatory for regulatory and reliability requirements.

The SRR0745A-121M from Bourns Inc. meets the inductance, tolerance, shielding, core material, package footprint, and compliance requirements. However, the current rating (600 mA) is lower than the main part specification.

Parameter Comparison

Engineering Selection Recommendations

Primary Part - SPD73R-124M: Select this part when the application requires the full 800 mA current rating, extended low-temperature operation down to -55°C, and the lower seated height of 3.90 mm is critical for PCB layout constraints.

Substitute Part - SRR0745A-121M: This Bourns inductor is suitable for applications where the current requirement does not exceed 600 mA continuous operation and saturation current does not exceed 700 mA. The superior DC resistance of 550 mOhm (versus 840 mOhm) results in lower resistive losses and reduced heat generation. The operating temperature range of -40 to 125°C is acceptable for applications not requiring extended low-temperature performance. The increased seated height of 4.70 mm must be verified against PCB clearance requirements. Both parts maintain Active product status and full RoHS3 compliance with MSL Level 1 rating.

Frequently Asked Questions (FAQ)

Q: Can the SRR0745A-121M directly replace the SPD73R-124M in all applications?

A: Direct replacement is limited by current rating. The SRR0745A-121M is rated for 600 mA continuous current versus 800 mA for the SPD73R-124M. Substitution is valid only when the application current requirement does not exceed 600 mA. Additionally, the operating temperature minimum of -40°C (versus -55°C) and increased seated height of 4.70 mm must be evaluated against application requirements.

Q: What is the significance of the DC Resistance (DCR) difference between these parts?

A: The SRR0745A-121M has a maximum DCR of 550 mOhm compared to 840 mOhm for the SPD73R-124M. Lower DCR reduces resistive losses, resulting in less heat generation and improved efficiency. This is a performance advantage of the substitute part.

Q: Are both parts RoHS3 compliant?

A: Yes, both the SPD73R-124M and SRR0745A-121M are RoHS3 compliant with MSL Level 1 (Unlimited) moisture sensitivity rating, meeting regulatory requirements for lead-free and restricted substance compliance.

Q: Does the height difference affect PCB assembly?

A: The SRR0745A-121M has a maximum seated height of 4.70 mm compared to 3.90 mm for the SPD73R-124M. This 0.80 mm difference must be verified against PCB layout, component clearance, and enclosure height constraints before substitution.

Q: What is the inductance tolerance for both parts?

A: Both parts are specified with ±20% inductance tolerance at 1 kHz test frequency. This tolerance must be considered in circuit design calculations for both the primary and substitute parts.

Q: Are there any certifications that differentiate these parts?

A: The SRR0745A-121M carries AEC-Q200 automotive qualification, while the SPD73R-124M does not list this certification in the provided specifications. This distinction is relevant for automotive or automotive-grade applications.