Littelfuse 39914000000 Equivalent & Substitute Parts

Part Overview

The Littelfuse 39914000000 is a 4A board mount fuse rated for 65V AC/DC operation with slow blow response characteristics. This through-hole radial fuse is designed for circuit protection in applications requiring moderate voltage and current ratings. The part maintains active product status with cULus approval and ROHS3 compliance. Substitute parts are identified when equivalent electrical performance can be achieved within the specified parameter tolerances while maintaining board mount through-hole radial configuration.

Substiute Parts

39914000000

Littelfuse Inc.In Stock: 75539914000000 Datasheet

Current PartRFQ

0697W4000-02

Bel Fuse Inc.In Stock: 25680697W4000-02 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the Littelfuse 39914000000 is determined by the following critical parameters:

Current Rating: 4 A (exact match required)

Response Time: Slow Blow (exact match required)

Mounting Type: Through Hole (exact match required)

Package Configuration: Radial, Box (exact match required)

Voltage Ratings: The substitute part must meet or exceed both AC and DC voltage requirements. The main part specifies 65V AC and 65V DC. Substitute parts with higher voltage ratings remain compatible for applications designed for the original voltage specification.

Physical Dimensions: Substitute parts must maintain compatibility with board mount through-hole radial footprints within standard tolerance ranges.

Compliance & Certifications: Substitute parts must maintain ROHS3 compliance and appropriate regulatory approvals for the target application.

Parameter Comparison

Engineering Selection Recommendations

The Bel Fuse 0697W4000-02 qualifies as a substitute for the Littelfuse 39914000000 based on matching current rating, response time, mounting type, and package configuration. The substitute part provides enhanced voltage ratings (350V AC / 72V DC) and extended operating temperature range (-55°C ~ 125°C), making it suitable for applications originally specified for the Littelfuse part.

Both parts maintain ROHS3 compliance and are active products. The Bel Fuse part carries additional regulatory approvals including AEC-Q200, CQC, cURus, PSE, and VDE, providing broader certification coverage for automotive and international applications.

Physical dimensions remain within compatible tolerance ranges for standard through-hole radial board mount footprints. The substitute part exhibits higher breaking capacity (100A vs 50A) and increased melting I²t (101 vs 75), indicating enhanced fault protection capability.

Frequently Asked Questions (FAQ)

Q: Can the Bel Fuse 0697W4000-02 be used as a direct replacement for the Littelfuse 39914000000?

A: Yes. Both parts share identical current rating (4A), response time (Slow Blow), mounting type (Through Hole), and package configuration (Radial, Box). The substitute part meets or exceeds the voltage specifications of the original part.

Q: What are the key differences between these two fuses?

A: The primary differences are voltage ratings (Bel Fuse provides 350V AC vs 65V AC), operating temperature range (Bel Fuse extends to -55°C ~ 125°C vs -40°C ~ 85°C), breaking capacity (100A vs 50A), and regulatory approvals. The Bel Fuse part is suitable for higher voltage applications and broader temperature environments.

Q: Are the physical dimensions compatible with existing board layouts?

A: The parts are dimensionally similar with minor variations within standard tolerance ranges. Littelfuse 39914000000 measures 8.50mm x 4.00mm x 8.00mm while Bel Fuse 0697W4000-02 measures 8.35mm x 4.00mm x 7.80mm. Both maintain through-hole radial configuration compatibility.

Q: What compliance certifications apply to each part?

A: Littelfuse 39914000000 carries cULus approval. Bel Fuse 0697W4000-02 carries AEC-Q200, CQC, cURus, PSE, and VDE approvals. Both parts are ROHS3 compliant and REACH unaffected.

Q: Does the higher DC cold resistance of the substitute part affect circuit performance?

A: The DC cold resistance difference (0.014 Ohms vs 0.01 Ohms) is minimal and remains within acceptable tolerance for board mount fuse applications. This parameter does not prevent substitution.

Q: Can the substitute part be used in applications rated for lower voltages?

A: Yes. The Bel Fuse 0697W4000-02 with 350V AC / 72V DC ratings is suitable for circuits originally specified for 65V AC / 65V DC operation. Higher voltage ratings provide compatibility with the original application requirements.