SSQ 12 /5K Equivalent & Substitute Parts

Part Overview

The SSQ 12 /5K is a 12 A, 125 V AC / 86 V DC surface mount board mount fuse manufactured by Bel Fuse Inc. This component is classified as obsolete, making identification of compatible substitute parts essential for ongoing system support and procurement planning. The fast-blow response characteristic and 2-SMD square end block package define its application scope in circuit protection applications requiring rapid fault isolation.

Substiute Parts

SSQ 12 /5K

Bel Fuse Inc.In Stock: 1181SSQ 12 /5K Datasheet

Current PartRFQ

0679L9120-05

Bel Fuse Inc.In Stock: 357170679L9120-05 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SSQ 12 /5K is determined by the following critical parameters:

• Current Rating: Must be 12 A to maintain circuit protection design intent
• Voltage Rating - AC: Must be 125 V or higher to ensure adequate voltage withstand capability
• Voltage Rating - DC: Must be 86 V or higher for DC circuit applications
• Response Time: Must be Fast Blow to match the original protection characteristic
• Mounting Type: Must be Surface Mount to ensure PCB assembly compatibility
• Package / Case: Must be 2-SMD, Square End Block to fit existing footprints
• Operating Temperature Range: Must encompass -55°C ~ 125°C for environmental compatibility

The substitute part 0679L9120-05 meets all these criteria while offering improved DC voltage rating (125 V DC versus 86 V DC) and enhanced breaking capacity specifications.

Parameter Comparison

Engineering Selection Recommendations

The 0679L9120-05 is a direct functional substitute for the obsolete SSQ 12 /5K. Both components share identical current ratings, AC voltage ratings, response characteristics, and mounting specifications. The substitute part offers enhanced DC voltage rating (125 V versus 86 V) and superior breaking capacity at rated voltage, providing improved performance margins in DC applications.

The substitute part carries AEC-Q200 automotive qualification and cURus certification, whereas the original part carries CE and cULus certifications. Selection between these parts should be based on specific application requirements and regulatory compliance mandates. The 0679L9120-05 is currently in active production status with substantial inventory availability (35,677 pcs), ensuring long-term supply continuity compared to the obsolete SSQ 12 /5K.

The 0.010" (0.25mm) height difference between parts is functionally negligible for surface mount assembly and does not impact PCB layout or thermal management considerations.

Frequently Asked Questions (FAQ)

Q: Can the 0679L9120-05 directly replace the SSQ 12 /5K in existing designs?

A: Yes. Both parts share identical current ratings (12 A), AC voltage ratings (125 V), response time (Fast Blow), mounting type (Surface Mount), and package configuration (2-SMD, Square End Block). The substitute part's enhanced DC voltage rating (125 V versus 86 V) and breaking capacity provide equivalent or superior performance in all specified operating conditions.

Q: What is the significance of the height difference between these parts?

A: The SSQ 12 /5K measures 0.100" H while the 0679L9120-05 measures 0.110" H. This 0.010" (0.25mm) difference is within standard PCB assembly tolerances and does not affect component placement, solder joint integrity, or thermal performance in typical board designs.

Q: Are the certifications interchangeable between these parts?

A: The SSQ 12 /5K carries CE and cULus certifications. The 0679L9120-05 carries AEC-Q200 and cURus certifications. Certification requirements depend on end-application regulatory mandates. Applications requiring specific certifications should confirm compliance before substitution.

Q: What is the inventory status difference between these parts?

A: The SSQ 12 /5K is obsolete with 1,097 pcs available. The 0679L9120-05 is in active production status with 35,677 pcs available, ensuring reliable long-term supply for new designs and ongoing production requirements.

Q: Are there electrical performance differences that affect circuit design?

A: Both parts maintain identical fast-blow response characteristics and 12 A current ratings. The substitute part's improved DC voltage rating (125 V versus 86 V) and breaking capacity (300A DC versus 10kA DC) provide enhanced performance margins without requiring circuit design modifications.