Littelfuse V511NA34 Equivalent & Substitute Parts

Part Overview

The Littelfuse V511NA34 is a 820 V, 40 kA transient voltage suppressor (TVS) varistor designed for surface mount applications in a square 34mm package. This component provides transient overvoltage protection in single-circuit configurations with 700 J energy absorption capability.

The V511NA34 carries an obsolete product status. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements for applications utilizing this varistor specification.

Substiute Parts

V511NA34

Littelfuse Inc.In Stock: 971V511NA34 Datasheet

Current PartRFQ

V511DHB34

Littelfuse Inc.In Stock: 694V511DHB34 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the V511NA34 is determined by strict equivalence across the following critical parameters:

• Varistor voltage rating (820 V nominal, with tolerance range 735 V to 910 V minimum to maximum)
• Surge current capacity (40 kA)
• Energy absorption (700 J)
• Maximum AC and DC voltage ratings (510 V AC, 675 V DC)
• Single-circuit configuration
• Capacitance specification (2500 pF @ 1 MHz)
• Operating temperature range (-55°C to 85°C)
• Square 34mm package geometry
• RoHS3 compliance

The primary substitute identified is the Littelfuse V511DHB34, which maintains electrical equivalence while differing in mounting technology (through-hole with tabs versus surface mount) and product status (active versus obsolete).

Parameter Comparison

Engineering Selection Recommendations

The V511DHB34 is the designated manufacturer substitute for the obsolete V511NA34. Both parts maintain identical electrical performance across all critical varistor parameters: 820 V nominal voltage, 40 kA surge current capacity, and 700 J energy absorption.

The primary design consideration is the transition from surface mount (V511NA34) to through-hole mounting with tabs (V511DHB34). This substitution requires PCB layout modification to accommodate the through-hole configuration and tab connections.

Both parts carry ROHS3 compliance and MSL 1 (unlimited moisture sensitivity), ensuring regulatory and environmental compatibility. The V511DHB34 holds active product status, providing long-term supply chain availability and manufacturing support.

Frequently Asked Questions (FAQ)

Q: Can the V511DHB34 directly replace the V511NA34 without circuit modification?

A: Electrical substitution is valid. However, PCB layout modification is required due to the change from surface mount to through-hole mounting technology. The tab connection points must be accommodated in the board design.

Q: Are the varistor voltage ratings identical between these parts?

A: The nominal varistor voltage is 820 V for both parts. Tolerance ranges differ slightly: V511NA34 ranges 735 V to 910 V, while V511DHB34 ranges 738 V to 902 V. Both ranges overlap and are functionally equivalent for the specified 820 V application.

Q: What is the significance of the product status change from obsolete to active?

A: The V511DHB34 active status indicates ongoing manufacturing, quality assurance, and supply chain support from Littelfuse Inc. This ensures component availability for new production orders and long-term design support.

Q: Are there compliance or certification differences between these parts?

A: Both parts are ROHS3 compliant with MSL 1 rating. The V511DHB34 includes REACH Unaffected status. No compliance barriers exist for substitution.

Q: What mounting considerations apply to the V511DHB34?

A: The V511DHB34 uses through-hole mounting with tabs. PCB design must include plated through-holes and tab connection pads. Mechanical support and solder joint design differ from surface mount applications.