SC105B-680 Equivalent & Substitute Parts

Part Overview

The SC105B-680 is a 68 µH unshielded wirewound inductor manufactured by Signal Transformer, rated for 1.35 A continuous current with a maximum DC resistance of 285mOhm. This component is classified as obsolete, making equivalent substitutes necessary for ongoing production and maintenance applications. The part operates across the industrial temperature range of -40°C to 125°C and is packaged in a nonstandard surface mount form factor measuring 10.90mm × 9.80mm × 6.00mm (max height).

Substiute Parts

SC105B-680

Signal TransformerIn Stock: 1025SC105B-680 Datasheet

Current PartRFQ

SRR1050A-680Y

Bourns Inc.In Stock: 13213SRR1050A-680Y Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The SRR1050A-680Y qualifies as a functional equivalent based on the following critical parameters:

Matching Parameters:

• Inductance value: 68 µH (identical)
• Operating temperature range: -40°C to 125°C (identical)
• Mounting type: Surface Mount (identical)
• RoHS3 compliance: Both parts meet this requirement
• Moisture sensitivity level: MSL 1 (Unlimited) for both parts

Allowable Variations:

• Current rating: SRR1050A-680Y rated at 1.6 A exceeds the SC105B-680 requirement of 1.35 A, providing design margin
• DC resistance: SRR1050A-680Y at 208 mOhm is lower than SC105B-680 at 285 mOhm, reducing power dissipation
• Inductance tolerance: SRR1050A-680Y at ±30% is wider than SC105B-680 at ±20%, but both fall within acceptable circuit design tolerances for this inductance value
• Physical dimensions: Slight variations in footprint (10.20mm × 10.00mm vs. 10.90mm × 9.80mm) remain within typical PCB layout tolerances for nonstandard packages

Parameter Comparison

Engineering Selection Recommendations

The SRR1050A-680Y is the designated manufacturer-recommended substitute for the obsolete SC105B-680. Selection of this substitute is supported by:

• Product Status Alignment: The SRR1050A-680Y maintains active production status, ensuring long-term availability and supply chain continuity
• Regulatory Compliance: Both parts meet ROHS3 and REACH requirements, maintaining compliance with current environmental standards
• Performance Margin: The substitute provides higher current rating (1.6 A vs. 1.35 A) and lower DC resistance (208 mOhm vs. 285 mOhm), delivering improved thermal performance in the application
• Certification: The SRR1050A-680Y carries AEC-Q200 qualification, indicating automotive-grade reliability testing

The shielded construction of the SRR1050A-680Y provides additional electromagnetic interference suppression compared to the unshielded SC105B-680, which may benefit noise-sensitive circuit applications.

Frequently Asked Questions (FAQ)

Q: Can the SRR1050A-680Y directly replace the SC105B-680 in existing designs?

A: Yes. Both parts share identical inductance values (68 µH), operating temperature ranges (-40°C to 125°C), and surface mount packaging. The substitute meets or exceeds all critical electrical parameters. Verify PCB footprint compatibility due to minor dimensional variations (10.20mm × 10.00mm vs. 10.90mm × 9.80mm).

Q: What is the impact of the wider inductance tolerance on the SRR1050A-680Y?

A: The SRR1050A-680Y tolerance of ±30% is wider than the SC105B-680 at ±20%. For applications requiring tighter inductance control, circuit design should accommodate this tolerance range. Both tolerances are standard for wirewound inductors in this inductance class.

Q: Does the shielded design of the SRR1050A-680Y affect circuit performance?

A: Shielding reduces electromagnetic radiation and susceptibility to external interference. In applications where the original unshielded design was selected for specific coupling characteristics, the shielded substitute may alter circuit behavior. Evaluate shielding impact based on circuit requirements.

Q: Are there packaging differences between these parts?

A: The SC105B-680 is supplied in standard inventory form, while the SRR1050A-680Y is available in Tape & Reel (TR) packaging. Both use nonstandard surface mount packages. Confirm packaging format compatibility with assembly equipment and procurement requirements.

Q: What is the significance of the AEC-Q200 rating on the SRR1050A-680Y?

A: AEC-Q200 certification indicates the part has undergone automotive-grade reliability testing. This qualification is not present on the obsolete SC105B-680 but provides additional assurance for applications requiring automotive or high-reliability standards.