V321NA34 Equivalent & Substitute Parts

Part Overview

The V321NA34 is a 510 V, 40 kA Transient Voltage Suppressor (TVS) varistor manufactured by Littelfuse Inc., designed for single-circuit surface mount applications in a square 34mm package. This component is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and new design implementations. The V321NA34 provides transient voltage suppression across a wide operating temperature range of -55°C to 85°C and maintains ROHS3 compliance with unlimited moisture sensitivity rating.

Substiute Parts

V321NA34

Littelfuse Inc.In Stock: 1085V321NA34 Datasheet

Current PartRFQ

V321DHB34

Littelfuse Inc.In Stock: 1082V321DHB34 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The V321DHB34 qualifies as a direct substitute for the V321NA34 based on the following critical electrical and mechanical parameters:

Electrical Equivalence Criteria:

• Identical varistor voltage rating: 510 V typical
• Identical maximum AC voltage: 320 V
• Identical maximum DC voltage: 420 V
• Identical surge current capacity: 40 kA
• Identical energy dissipation: 460 J
• Identical capacitance: 3800 pF @ 1 MHz
• Identical operating temperature range: -55°C to 85°C

Mechanical Compatibility:

• Identical package form factor: Square 34mm
• Single circuit configuration maintained

Compliance Alignment:

• Both parts maintain ROHS3 compliance
• Both parts carry unlimited moisture sensitivity rating (MSL 1)

The primary distinction between these parts is the mounting technology: the V321NA34 uses surface mount technology, while the V321DHB34 employs through-hole mounting with tabs. This difference requires PCB design modification but does not affect electrical performance or functional capability.

Parameter Comparison

Engineering Selection Recommendations

The V321DHB34 is the designated manufacturer substitute for the obsolete V321NA34. Both components maintain identical electrical performance specifications across all critical parameters: voltage ratings, surge current capacity, energy dissipation, and operating temperature range. Both parts satisfy ROHS3 compliance requirements and carry unlimited moisture sensitivity ratings.

The V321DHB34 carries active product status, ensuring continued availability and manufacturing support. Selection of the V321DHB34 requires PCB redesign to accommodate through-hole mounting with tabs in place of surface mount technology. This substitution is appropriate for applications where PCB layout modification is feasible and where the through-hole mounting approach meets mechanical assembly requirements.

Frequently Asked Questions (FAQ)

Q: Can the V321DHB34 directly replace the V321NA34 without PCB modification?

A: No. The V321NA34 is surface mount, while the V321DHB34 is through-hole with tabs. PCB layout and footprint redesign is required. However, electrical performance is identical.

Q: Are the electrical specifications identical between these parts?

A: Yes. Both parts share identical varistor voltage ratings (510 V typical), maximum AC/DC voltage limits (320 V / 420 V), surge current capacity (40 kA), energy dissipation (460 J), and operating temperature range (-55°C to 85°C).

Q: What is the significance of the varistor voltage minimum tolerance difference (462 V vs. 459 V)?

A: The 3 V difference falls within acceptable manufacturing tolerance for varistor components and does not affect functional equivalence for this application category. Both parts maintain the same typical and maximum voltage specifications.

Q: Does the V321DHB34 meet the same compliance standards?

A: Yes. Both parts are ROHS3 compliant and carry identical moisture sensitivity levels (MSL 1, Unlimited).

Q: Why is the V321NA34 classified as obsolete?

A: The V321NA34 has reached end-of-life status. The V321DHB34 represents the active product line continuation from Littelfuse Inc. for this voltage and current rating class.

Q: Are there any thermal or environmental performance differences?

A: No. Both parts operate across the identical temperature range of -55°C to 85°C and maintain equivalent thermal and environmental performance characteristics.