400CC1206LR-C-2 Equivalent & Substitute Parts

Part Overview

The 400CC1206LR-C-2 is a Polymeric PTC Resettable Fuse manufactured by Littelfuse Inc., designed for surface mount applications in the 1206 (3216 Metric) package. This component provides overcurrent protection with a maximum voltage rating of 21V and a hold current of 4A. The part is currently listed as obsolete, making identification of suitable substitute components essential for ongoing design support and production continuity.

Substiute Parts

400CC1206LR-C-2

Littelfuse Inc.In Stock: 1062400CC1206LR-C-2 Datasheet

Current PartRFQ

1206L400/12SLWR

Littelfuse Inc.In Stock: 63611206L400/12SLWR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 400CC1206LR-C-2 is determined by the following critical parameters:

Mandatory Compatibility Criteria:

• Package type: 1206 (3216 Metric) surface mount
• Current rating: Hold current (Ih) of 4A
• Mounting configuration: Surface mount technology
• Approval certifications: cURus and TUV compliance

Allowable Parameter Variations:

• Voltage rating: The substitute may have a lower maximum voltage rating provided it meets or exceeds the application's actual operating voltage
• Resistance characteristics: Initial and post-trip resistance values may differ within acceptable operating margins
• Operating temperature range: May be extended or equivalent
• Moisture sensitivity level: May be improved (lower MSL value)
• Product status: Active parts are preferred over obsolete parts for long-term availability

The 1206L400/12SLWR meets these criteria as a direct substitute, maintaining the same package footprint, current rating, and surface mount configuration while offering improved product status and availability.

Parameter Comparison

Engineering Selection Recommendations

The 1206L400/12SLWR is the recommended substitute for the obsolete 400CC1206LR-C-2 based on the following engineering factors:

Product Status & Availability: The substitute part is active and currently in production, ensuring long-term supply chain continuity. The main part is obsolete, creating sourcing risk for new designs and production runs.

Regulatory Compliance: Both parts maintain cURus and TUV approvals and are ROHS3 compliant, meeting regulatory requirements for equivalent applications.

Functional Equivalence: Both components share identical hold current ratings (4A) and surface mount 1206 package configuration, ensuring mechanical and electrical compatibility in PCB layouts.

Voltage Consideration: The substitute operates at a maximum of 12V compared to the main part's 21V rating. This substitution is valid only for applications where the actual circuit voltage does not exceed 12V. For circuits operating above 12V, alternative parts with higher voltage ratings must be sourced.

Moisture Handling: The substitute offers improved moisture sensitivity (MSL 1 vs. 2A), providing better performance in humid storage and assembly environments.

Thermal Range: The substitute extends the lower operating temperature limit to -40°C, providing broader environmental compatibility.

Frequently Asked Questions (FAQ)

Q: Can the 1206L400/12SLWR replace the 400CC1206LR-C-2 in all applications?

A: The 1206L400/12SLWR is a direct substitute only for applications where the circuit voltage does not exceed 12V. The main part is rated for 21V maximum. If your circuit operates above 12V, the substitute is not appropriate.

Q: What is the difference between the two parts' resistance specifications?

A: The 1206L400/12SLWR has a lower initial resistance (3 mOhms vs. 4 mOhms) and higher post-trip resistance (16 mOhms vs. 10 mOhms). Both values remain within acceptable operating margins for polymeric PTC fuse applications. The differences reflect design variations between the LoRho and POLY-FUSE series.

Q: Are there package footprint differences I should consider?

A: Both parts use the 1206 (3216 Metric) package. The substitute has a concave profile and is slightly thicker (0.055" vs. 0.032"). Verify that your PCB layout and assembly process accommodate the increased thickness before implementation.

Q: Why is the main part listed as obsolete?

A: Obsolescence typically results from manufacturer discontinuation due to product line consolidation, market demand shifts, or replacement by improved alternatives. The substitute represents Littelfuse's current active offering in this category.

Q: Does the improved MSL rating affect my assembly process?

A: The substitute's MSL 1 rating (unlimited shelf life) is superior to the main part's MSL 2A (4-week limit). This reduces moisture-related handling constraints and improves component reliability in storage and assembly environments.

Q: Are both parts certified for the same regulatory standards?

A: Yes. Both the 400CC1206LR-C-2 and 1206L400/12SLWR carry cURus and TUV approvals and are ROHS3 compliant, meeting equivalent regulatory requirements.