Littelfuse 06643.15HXSL Equivalent & Substitute Parts

Part Overview

The Littelfuse 06643.15HXSL is a 3.15 A, 250 V AC/DC board mount fuse with slow blow response characteristics, designed for through-hole radial mounting in a vertical can configuration. This part is classified as obsolete, making identification of active equivalent components essential for ongoing design support and procurement continuity. The substitute part 38213150410 from the TR5® 382 series provides functional equivalence while maintaining active product status.

Substiute Parts

06643.15HXSL

Littelfuse Inc.In Stock: 93106643.15HXSL Datasheet

Current PartRFQ

38213150410

Littelfuse Inc.In Stock: 136338213150410 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 06643.15HXSL is determined by strict equivalence across the following critical parameters:

Current Rating: 3.15 A (exact match required) Voltage Rating: 250 V AC (exact match required) Response Time: Slow Blow (exact match required) Mounting Type: Through Hole (exact match required) Package Configuration: Radial, Can, Vertical (exact match required) Breaking Capacity: 100 A @ rated voltage (exact match required) Operating Temperature: -40°C ~ 85°C (exact match required)

The substitute part 38213150410 meets all these criteria. Physical dimensions vary slightly (height: 0.333" vs. 0.315"), and electrical characteristics such as melting I²t and DC cold resistance differ within acceptable tolerances for the same functional class. Both parts maintain ROHS3 compliance and operate across the identical temperature range.

Parameter Comparison

Engineering Selection Recommendations

The 38213150410 is the direct active equivalent for the obsolete 06643.15HXSL. Both parts are manufactured by Littelfuse Inc. and share identical electrical ratings, response characteristics, and mounting specifications. The substitute part carries active product status, ensuring long-term availability and supply chain continuity.

Selection of 38213150410 is supported by:

Identical current and voltage ratings (3.15 A, 250 V AC) Matching slow blow response time and breaking capacity (100 A) Equivalent operating temperature range (-40°C ~ 85°C) ROHS3 compliance maintained across both parts Regulatory approvals covering industrial and consumer applications (CCC, CSA, KTL, METI, SEMKO, UL, VDE for original; CCC, cURus, KC, PSE/JET, SEMKO, VDE for substitute)

Physical dimensions are compatible with standard through-hole radial fuse footprints. The minor height reduction (0.333" to 0.315") presents no mechanical interference risk in typical board mount applications.

Frequently Asked Questions (FAQ)

Q: Can 38213150410 be used as a direct replacement for 06643.15HXSL in existing designs?

A: Yes. Both parts are 3.15 A, 250 V AC slow blow fuses with identical mounting type, package configuration, and breaking capacity. The substitute maintains the same electrical performance class and operating temperature range.

Q: What is the significance of the different melting I²t values (57 vs. 45.35)?

A: Melting I²t represents the thermal energy required to melt the fuse element. The variation reflects different internal element designs between the LT-5™ 664 and TR5® 382 series, but both parts are classified as slow blow and meet the same 3.15 A current rating specification. This difference does not affect functional equivalence for standard circuit protection applications.

Q: Are there dimensional compatibility concerns with the height difference?

A: The height reduction from 0.333" to 0.315" is within standard tolerance for radial can fuses and presents no mechanical interference in conventional through-hole board mount applications. Verify clearance in space-constrained designs.

Q: What regulatory certifications apply to the substitute part?

A: The 38213150410 carries approvals from CCC, cURus, KC, PSE/JET, SEMKO, and VDE. These certifications cover industrial, consumer, and regional market requirements. Confirm that the specific certification set meets your application's regulatory requirements.

Q: Why is the original part obsolete?

A: The 06643.15HXSL from the LT-5™ 664 series has been discontinued by Littelfuse Inc. The TR5® 382 series (38213150410) represents the current active product line for this functional specification, ensuring ongoing availability and manufacturing support.

Q: Is the DC cold resistance difference significant?

A: The DC cold resistance values (0.02 Ohms vs. 0.0176 Ohms) reflect minor design variations between series. Both values are within acceptable limits for slow blow fuses in this current class and do not impact circuit protection performance or thermal characteristics in standard applications.