SC105B-330 Equivalent & Substitute Parts

Part Overview

The SC105B-330 is a 33 µH unshielded wirewound inductor manufactured by Signal Transformer, rated for 1.9 A continuous current with a maximum DC resistance of 160mOhm. This component is classified as obsolete, making substitute parts necessary for new designs and ongoing production requirements. The part operates across the industrial temperature range of -40°C to 125°C and is packaged in a nonstandard surface mount configuration measuring 10.90mm × 9.80mm × 6.00mm.

Substiute Parts

SC105B-330

Signal TransformerIn Stock: 818SC105B-330 Datasheet

Current PartRFQ

SRR1050A-330Y

Bourns Inc.In Stock: 2628SRR1050A-330Y Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The SRR1050A-330Y qualifies as a direct substitute based on the following critical parameters:

Matching Parameters:

• Inductance value: 33 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-330Y rated at 2.5 A exceeds the SC105B-330 requirement of 1.9 A, providing design margin
• DC resistance: SRR1050A-330Y at 93mOhm is lower than SC105B-330 at 160mOhm, reducing power dissipation
• Shielding: SRR1050A-330Y is shielded versus unshielded SC105B-330, providing electromagnetic isolation benefits
• Inductance tolerance: SRR1050A-330Y at ±30% is wider than SC105B-330 at ±20%, but remains within acceptable engineering margins for 33 µH applications

Parameter Comparison

Engineering Selection Recommendations

The SRR1050A-330Y from Bourns Inc. is the qualified substitute for the obsolete SC105B-330. Selection is based on:

• Product Status: SRR1050A-330Y maintains active production status, ensuring long-term availability and supply chain continuity
• Compliance: Both parts meet ROHS3 requirements and carry identical moisture sensitivity ratings (MSL 1)
• Electrical Performance: The substitute provides superior electrical characteristics with lower DC resistance (93mOhm vs 160mOhm) and higher current capacity (2.5 A vs 1.9 A), enabling direct replacement in existing circuit designs
• Mechanical Compatibility: Physical dimensions are comparable with the substitute slightly more compact in height (5.10mm vs 6.00mm), accommodating standard PCB layouts
• Certifications: SRR1050A-330Y carries AEC-Q200 automotive qualification, providing additional reliability assurance

Frequently Asked Questions (FAQ)

Q: Can the SRR1050A-330Y directly replace the SC105B-330 in existing designs?

A: Yes. Both parts share identical inductance values (33 µH), operating temperature ranges (-40°C to 125°C), and surface mount packaging. The substitute's higher current rating and lower DC resistance provide improved performance margins.

Q: What is the impact of the shielding difference?

A: The SC105B-330 is unshielded while the SRR1050A-330Y is shielded. Shielding reduces electromagnetic coupling to adjacent components and traces, which is beneficial in most applications. If the original design specifically required an unshielded inductor for coupling purposes, this difference must be evaluated in circuit context.

Q: Does the inductance tolerance difference affect substitution?

A: The SC105B-330 specifies ±20% tolerance while the SRR1050A-330Y specifies ±30%. For 33 µH inductors, this represents a variation range of ±6.6 µH versus ±9.9 µH respectively. Applications with tight inductance requirements must account for this wider tolerance in the substitute part.

Q: Are there packaging considerations for PCB layout?

A: Both parts use nonstandard surface mount packages with comparable footprints (10.90mm × 9.80mm versus 10.20mm × 10.00mm). The substitute is slightly shorter (5.10mm versus 6.00mm seated height), which may provide additional clearance in space-constrained designs.

Q: What certifications does the substitute carry?

A: The SRR1050A-330Y carries AEC-Q200 automotive qualification in addition to ROHS3 compliance, providing enhanced reliability documentation suitable for automotive and industrial applications.