TMOV34S321EP Equivalent & Substitute Parts

Part Overview

The TMOV34S321EP is a 510 V, 40 kA Transient Voltage Suppressor (TVS) varistor manufactured by Littelfuse Inc. in the TMOV® 34S series. This through-hole component is designed for transient overvoltage protection in industrial and commercial applications. The part is currently Active in product status with 932 units in stock. Alternative models are identified to support supply chain flexibility and component availability across equivalent performance specifications.

Substiute Parts

TMOV34S321EP

Littelfuse Inc.In Stock: 948TMOV34S321EP Datasheet

Current PartRFQ

V321HB34

Littelfuse Inc.In Stock: 1004V321HB34 Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the TMOV34S321EP is determined by the following critical parameters:

• Varistor Voltage Range: 459 V (Min) to 561 V (Max)
• Current - Surge Capacity: 40 kA
• Package / Case: Square 34mm, Formed Tabs
• Mounting Type: Through Hole
• Number of Circuits: 1
• Operating Temperature Range: -55°C to 85°C
• Compliance: ROHS3 Compliant, REACH Unaffected

The identified substitute part V321HB34 meets all critical electrical and mechanical parameters within the allowed tolerance bands, enabling direct functional equivalence in circuit applications.

Parameter Comparison

Engineering Selection Recommendations

Both TMOV34S321EP and V321HB34 are Active products from Littelfuse Inc. with full ROHS3 compliance and REACH unaffected status. Selection between these parts should be based on:

• Inventory availability and lead time requirements
• Energy dissipation requirements: TMOV34S321EP provides 640 J versus V321HB34 at 460 J
• Application-specific thermal management constraints
• Supply chain sourcing preferences

Both parts satisfy identical electrical specifications, mechanical form factors, and regulatory compliance requirements for direct substitution in through-hole circuit applications.

Frequently Asked Questions (FAQ)

Q: Can V321HB34 be used as a direct replacement for TMOV34S321EP?

A: Yes. Both parts share identical varistor voltage ratings (510 V typical), surge current capacity (40 kA), package dimensions (Square 34mm, Formed Tabs), and operating temperature range (-55°C to 85°C). The primary difference is energy dissipation capacity.

Q: What is the difference in energy rating between these parts?

A: TMOV34S321EP is rated at 640 J, while V321HB34 is rated at 460 J. Applications requiring higher energy absorption should specify TMOV34S321EP.

Q: Are both parts through-hole mounted?

A: Yes. Both TMOV34S321EP and V321HB34 use through-hole mounting with Square 34mm, Formed Tabs package configuration.

Q: Do both parts meet RoHS compliance?

A: Yes. Both parts are ROHS3 Compliant and REACH Unaffected, meeting current environmental and regulatory standards.

Q: What is the operating temperature range for these varistors?

A: Both parts operate across -55°C to 85°C ambient temperature range.

Q: Are there any differences in electrical specifications between these parts?

A: Electrical specifications are identical: Maximum AC Volts (320 V), Maximum DC Volts (420 V), Varistor Voltage range (459 V to 561 V), Current - Surge (40 kA), and Capacitance @ 1 MHz (3800 pF).