SCR105B-120 Equivalent & Substitute Parts

Part Overview

The SCR105B-120 is a 12 µH shielded inductor manufactured by Signal Transformer, rated for 4 A continuous current with a maximum DC resistance of 70 mOhm. This surface mount component operates across the industrial temperature range of -40°C to 125°C and is ROHS3 compliant. The part is currently obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and procurement.

Substiute Parts

SCR105B-120

Signal TransformerIn Stock: 1197SCR105B-120 Datasheet

Current PartRFQ

SRR1050A-120Y

Bourns Inc.In Stock: 1224SRR1050A-120Y Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SCR105B-120 is determined by the following critical parameters:

• Inductance Value: 12 µH (exact match required)
• Current Rating: Minimum 4 A continuous current capability
• DC Resistance: Maximum 70 mOhm to maintain circuit performance
• Shielding: Shielded construction for EMI containment
• Mounting: Surface mount package compatibility
• Temperature Range: -40°C to 125°C operational capability
• Compliance: ROHS3 and REACH compliance status

The SRR1050A-120Y from Bourns Inc. meets these substitution criteria with equivalent inductance, shielded construction, and compatible operating temperature range. While the current rating is slightly lower at 3.8 A and DCR is improved at 35 mOhm, the part remains functionally suitable for applications within its rated specifications.

Parameter Comparison

Engineering Selection Recommendations

The SRR1050A-120Y is the manufacturer-recommended substitute for the obsolete SCR105B-120. Both components maintain ROHS3 compliance and REACH unaffected status, ensuring regulatory continuity. The substitute offers improved DC resistance performance at 35 mOhm compared to the original 70 mOhm specification, resulting in lower power dissipation. The current rating differential of 3.8 A versus 4 A requires verification that the application does not demand the full 4 A continuous rating. Both parts operate identically across the -40°C to 125°C temperature range and maintain shielded construction for equivalent EMI performance. Active product status of the SRR1050A-120Y ensures long-term availability and supply chain stability.

Frequently Asked Questions (FAQ)

Q: Can the SRR1050A-120Y directly replace the SCR105B-120 in existing designs?

A: Direct substitution is possible when the application current requirement does not exceed 3.8 A continuous. The inductance value, shielding, temperature range, and compliance certifications are equivalent. Physical dimensions differ slightly, requiring PCB layout verification.

Q: What is the impact of the 0.2 A current rating reduction?

A: The SRR1050A-120Y is rated for 3.8 A versus the original 4 A. Applications operating below 3.8 A continuous current experience no functional impact. Designs requiring the full 4 A rating must be re-evaluated or alternative parts sourced.

Q: How does the improved DC resistance affect circuit performance?

A: The SRR1050A-120Y DCR of 35 mOhm is superior to the original 70 mOhm specification. This reduction decreases resistive losses and heat generation, improving overall circuit efficiency without requiring design changes.

Q: Are there physical dimension compatibility concerns?

A: The SCR105B-120 measures 10.50mm L x 9.50mm W x 5.50mm H, while the SRR1050A-120Y measures 10.20mm L x 10.00mm W x 5.10mm H. PCB footprint and clearance verification is required before implementation.

Q: What is the inductance tolerance difference impact?

A: The SCR105B-120 specifies ±20% tolerance while the SRR1050A-120Y specifies ±30%. Applications with tight inductance requirements must account for the wider tolerance band of the substitute part.

Q: Are packaging and moisture sensitivity equivalent?

A: Both components feature MSL 1 (Unlimited) moisture sensitivity rating. The SCR105B-120 uses nonstandard packaging while the SRR1050A-120Y is supplied in Tape & Reel format, affecting procurement and handling procedures.