SL1122A260R Gas Discharge Tube Equivalent & Substitute Parts

Part Overview

The SL1122A260R is a 3-pole gas discharge tube (GDT) rated for 260V DC spark-over voltage with 10kA impulse discharge current capacity. This component is designed for through-hole mounting in radial cylinder configuration and provides overvoltage protection in industrial and telecommunications applications.

The SL1122A260R is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production or field replacement requirements.

Substiute Parts

SL1122A260R

LittelfuseIn Stock: 779SL1122A260R Datasheet

Current PartRFQ

SL1021A260R

LittelfuseIn Stock: 1755SL1021A260R Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SL1122A260R is based on electrical and mechanical parameter equivalence. The following criteria determine functional interchangeability:

• Voltage rating: 260V DC spark-over voltage (nominal)
• Discharge current capacity: 10kA impulse current (8/20µs waveform)
• Pole configuration: 3-pole architecture
• Mounting method: Through-hole technology
• Fail mode: Non-shorting characteristic
• Environmental compliance: ROHS3 compliance and MSL rating

The SL1021A260R meets all these core substitution criteria. The primary difference is the package configuration: the SL1122A260R uses a radial cylinder 3-lead package, while the SL1021A260R uses an axial cylinder 3-lead package with radial bend. Both configurations are through-hole mounted and electrically equivalent.

Parameter Comparison

Engineering Selection Recommendations

The SL1021A260R is the manufacturer-recommended substitute for the obsolete SL1122A260R. Both parts are manufactured by Littelfuse and maintain identical electrical specifications: 260V DC spark-over voltage, 10kA impulse discharge current, and 3-pole configuration.

The SL1021A260R carries active product status, ensuring ongoing availability and supply chain support. Both parts maintain ROHS3 compliance and MSL Level 1 rating, meeting environmental and reliability requirements.

The primary consideration for substitution is PCB layout accommodation. The SL1122A260R uses a radial cylinder package, while the SL1021A260R uses an axial cylinder package with radial bend. PCB footprint and lead spacing must be evaluated to confirm mechanical compatibility with existing board designs.

Frequently Asked Questions (FAQ)

Q: Are the SL1122A260R and SL1021A260R electrically identical?

A: Yes. Both parts share identical electrical specifications: 260V DC spark-over voltage, 10kA impulse discharge current (8/20µs), 3-pole configuration, and non-shorting fail mode. They are functionally equivalent for overvoltage protection applications.

Q: What is the primary difference between these two parts?

A: The package configuration differs. The SL1122A260R is a radial cylinder design, while the SL1021A260R is an axial cylinder design with radial bend. Both are through-hole mounted, but lead geometry and PCB footprint spacing vary.

Q: Can I use the SL1021A260R as a direct replacement on existing PCBs designed for the SL1122A260R?

A: PCB compatibility depends on footprint design. The axial cylinder package with radial bend of the SL1021A260R may require different lead hole spacing than the radial cylinder package of the SL1122A260R. Physical verification of lead positioning and hole alignment is necessary before board-level substitution.

Q: Why is the SL1122A260R obsolete while the SL1021A260R remains active?

A: Littelfuse has transitioned the SL1122A series to obsolescence while maintaining the SL1021A series in active production. The SL1021A260R is the current production equivalent and recommended substitute for new designs and field replacements.

Q: Are both parts RoHS compliant?

A: Yes. Both the SL1122A260R and SL1021A260R are ROHS3 compliant and carry MSL Level 1 (Unlimited) moisture sensitivity rating.