SH90 Gas Discharge Tube - Equivalent & Substitute Parts

Part Overview

The SH90 is a 90V, 5kA Gas Discharge Tube (GDT) manufactured by Littelfuse in a 2-pole surface mount configuration. This component is designed for overvoltage protection applications requiring fast transient suppression. The part is currently in active production status with full RoHS3 compliance and unlimited moisture sensitivity rating. Substitute parts are identified when equivalent electrical performance and mechanical compatibility are required due to inventory constraints, supply chain considerations, or design flexibility needs.

Substiute Parts

SH90

LittelfuseIn Stock: 860SH90 Datasheet

Current PartRFQ

2035-09-SM-RPLF

Bourns Inc.In Stock: 601892035-09-SM-RPLF Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The 2035-09-SM-RPLF manufactured by Bourns Inc. qualifies as a direct substitute for the SH90 based on the following critical parameters:

• Voltage - DC Spark Over (Nominal): 90 V (identical)
• Impulse Discharge Current (8/20µs): 5000A (5kA) (identical)
• Number of Poles: 2 (identical)
• Mounting Type: Surface Mount (identical)
• Fail Mode: No Fail Short (identical)
• RoHS3 Compliance: Both parts meet ROHS3 requirements
• Moisture Sensitivity Level: 1 (Unlimited) for both parts
• REACH Status: Both parts are REACH Unaffected

The substitute part operates within the same electrical performance envelope and maintains mechanical compatibility for PCB assembly processes.

Parameter Comparison

Engineering Selection Recommendations

Both the SH90 and 2035-09-SM-RPLF are active production components with identical electrical specifications for 90V, 5kA overvoltage protection. Selection between these parts should be based on:

• Availability and lead time requirements
• PCB layout constraints related to package geometry (Square End Block vs. Cylinder Square End)
• Supply chain preferences and established vendor relationships
• Compliance requirements: Both parts meet ROHS3 and REACH standards

The Bourns 2035-09-SM-RPLF includes a specified tolerance of ±20% on the spark-over voltage, whereas the Littelfuse SH90 tolerance is not specified in the provided data. This tolerance specification should be evaluated against circuit design margins if voltage regulation precision is critical to the application.

Frequently Asked Questions (FAQ)

Q: Can the 2035-09-SM-RPLF be used as a direct replacement for the SH90 in existing designs?

A: Yes. Both parts share identical electrical performance specifications (90V spark-over voltage, 5kA impulse discharge current, 2-pole configuration) and are both surface mount components. PCB layout may require minor adjustment due to package geometry differences (Square End Block vs. Cylinder Square End), but electrical functionality is equivalent.

Q: What is the significance of the ±20% tolerance specification on the Bourns part?

A: The Bourns 2035-09-SM-RPLF specifies a ±20% tolerance on the DC spark-over voltage, meaning the actual spark-over voltage can range from 72V to 108V. The Littelfuse SH90 tolerance is not specified in the provided documentation. Circuit designs should account for this tolerance range when selecting between these parts.

Q: Are there any compliance or regulatory differences between these parts?

A: No. Both parts are ROHS3 compliant, REACH unaffected, and carry identical moisture sensitivity ratings (MSL 1 - Unlimited). Both are classified under ECCN EAR99 and HTSUS 8536.30.8000.

Q: What are the package differences between these two parts?

A: The SH90 uses a 2-SMD, Square End Block package, while the 2035-09-SM-RPLF uses a 2-SMD Cylinder Square End package. Both are surface mount configurations suitable for automated PCB assembly, but physical dimensions and footprint may differ. Verify PCB layout compatibility before substitution.

Q: Which part should be selected for new designs?

A: Selection should be based on component availability, supply chain strategy, and specific package requirements for your PCB layout. Both parts are in active production and meet all relevant compliance standards. Consult current inventory levels and lead times from your component distributor.