SPD125-124M Equivalent & Substitute Parts

Part Overview

The SPD125-124M is a 120 µH shielded inductor manufactured by API Delevan Inc., rated for 1.1 A maximum current with 250mOhm maximum DC resistance. This component is designed for surface mount applications in nonstandard package configurations. The part is currently classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing design support and procurement planning. Substitute parts must maintain electrical performance within the specified operating parameters while accommodating modern supply chain availability.

Substiute Parts

SPD125-124M

API Delevan Inc.In Stock: 956SPD125-124M Datasheet

Current PartRFQ

SRR1206-121YL

Bourns Inc.In Stock: 892SRR1206-121YL Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SPD125-124M is based on the following critical electrical and mechanical parameters:

Primary Matching Criteria:

• Inductance value: 120 µH (exact match required)
• Shielding configuration: Shielded (electromagnetic containment requirement)
• Core material: Ferrite (magnetic performance and frequency response)
• Mounting technology: Surface Mount (PCB assembly compatibility)
• Current rating: Minimum 1.1 A (load capacity requirement)
• DC resistance: Maximum 260mOhm (power dissipation tolerance)
• Operating temperature range: Minimum -40°C ~ 125°C (thermal compatibility)

The SRR1206-121YL from Bourns Inc. meets these substitution criteria. Both components share identical inductance values, ferrite core construction, shielded configuration, and surface mount technology. The substitute part demonstrates superior current saturation rating (1.8A vs. 1.1A) and lower inductance tolerance (±15% vs. ±20%), providing enhanced performance margins.

Parameter Comparison

Engineering Selection Recommendations

SRR1206-121YL Selection Basis:

The SRR1206-121YL qualifies as a functional substitute based on the following engineering factors:

1. Electrical Equivalence: Identical 120 µH inductance value with superior inductance tolerance (±15% vs. ±20%) ensures consistent circuit performance. The substitute's higher saturation current (1.8A) provides operational margin above the 1.1A requirement.

2. Product Status: The substitute part maintains active production status with Bourns Inc., ensuring long-term availability and supply chain stability. The original SPD125-124M is obsolete, making this transition necessary for sustained component sourcing.

3. Regulatory Compliance: The SRR1206-121YL is ROHS3 compliant, meeting current environmental and regulatory standards. The original part is RoHS non-compliant, presenting compliance risks in modern manufacturing environments.

4. Physical Compatibility: Both components utilize surface mount technology with comparable footprints (12.00mm vs. 12.70mm length; 12.00mm vs. 12.70mm width) and heights (6.00mm vs. 6.50mm). Minor dimensional differences are within typical PCB layout tolerances for nonstandard packages.

5. Thermal Performance: The substitute operates across -40°C ~ 125°C, covering the upper temperature requirement of the original specification. Applications requiring the full -55°C lower limit require verification of circuit-level thermal requirements.

Frequently Asked Questions (FAQ)

Q: Can the SRR1206-121YL directly replace the SPD125-124M in existing designs?

A: The SRR1206-121YL meets the core electrical requirements (120 µH inductance, shielded ferrite core, 1.1A+ current capability). Physical dimensions are similar but not identical (12.70mm vs. 12.00mm). PCB layout verification is required to confirm footprint compatibility with the nonstandard package configuration.

Q: What is the impact of the substitute's 1 A rated current versus the original 1.1 A?

A: The rated current specification differs by 0.1 A. However, the substitute's saturation current (Isat) is 1.8A, exceeding both the original saturation rating and the 1.1A requirement. Circuit-level current analysis must confirm that actual operating current does not exceed 1 A continuous rating.

Q: Does the ±15% inductance tolerance of the substitute affect circuit performance?

A: The tighter tolerance (±15% vs. ±20%) of the substitute provides improved consistency. Circuits designed for the original ±20% tolerance will operate within acceptable parameters with the substitute's ±15% tolerance.

Q: Are there thermal limitations with the substitute's -40°C lower operating limit?

A: The original part specifies -55°C ~ 125°C; the substitute specifies -40°C ~ 125°C. Applications requiring operation below -40°C must evaluate circuit-level thermal requirements and confirm the substitute's suitability for the specific thermal environment.

Q: What packaging format is the substitute supplied in?

A: The SRR1206-121YL is supplied in Tape & Reel (TR) format, standard for high-volume surface mount assembly. The original part packaging format is not specified in available documentation.

Q: Is the substitute RoHS compliant?

A: Yes, the SRR1206-121YL is ROHS3 compliant. The original SPD125-124M is RoHS non-compliant. This compliance difference is significant for applications subject to environmental regulations or customer RoHS requirements.