977-025-020-121 D-Sub Backshell Connector Equivalent & Substitute Parts

Part Overview

The 977-025-020-121 is a 25-position two-piece backshell connector manufactured by NorComp Inc., designed for D-Sub applications with 180° cable exit and shielded configuration. This component is classified as obsolete, which necessitates identification of active equivalent parts to maintain supply chain continuity and ensure long-term component availability for new designs and field replacements.

Substiute Parts

977-025-020-121

NorComp Inc.In Stock: 927977-025-020-121 Datasheet

Current PartRFQ

977-025-020R121

NorComp Inc.In Stock: 17988977-025-020R121 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 977-025-020-121 is determined by strict equivalence across the following critical parameters:

• Number of Positions: 25
• Accessory Type: Two Piece Backshell
• Compatible Shell Size: B
• Compatible D-Sub Size: 25pos and HD44pos
• Cable Exit Angle: 180°
• Shielding Configuration: Shielded
• Cable Type: Round
• Plating Specification: Nickel over Copper
• Hardware: Assembly Hardware, Strain Relief with 4-40 Mating Screws
• Color: Silver

The substitute part 977-025-020R121 maintains identical electrical and mechanical specifications across all these parameters, with the primary distinction being product status transition from obsolete to active and improved regulatory compliance.

Parameter Comparison

Engineering Selection Recommendations

The 977-025-020R121 is the direct active equivalent for the obsolete 977-025-020-121. Selection of the substitute part is supported by:

• Identical mechanical and electrical specifications across all functional parameters
• Active product status ensuring ongoing availability and supply chain support
• ROHS3 compliance, addressing regulatory requirements for new designs and applications subject to RoHS directives
• Improved moisture sensitivity level rating (MSL 1 - Unlimited) providing enhanced handling flexibility
• Bulk packaging availability supporting production requirements

For applications where RoHS non-compliance is a specific requirement, the original 977-025-020-121 remains available in limited inventory (824 Pcs). However, for new designs and standard applications, the 977-025-020R121 is the recommended selection.

Frequently Asked Questions (FAQ)

Q: Are the 977-025-020-121 and 977-025-020R121 mechanically interchangeable?

A: Yes. Both parts maintain identical specifications for number of positions (25), shell size (B), cable exit angle (180°), shielding configuration, plating (Nickel over Copper), and hardware (4-40 mating screws). Direct substitution is supported without design modification.

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

A: The 977-025-020R121 is the active production equivalent with ROHS3 compliance and MSL 1 rating, while the 977-025-020-121 is obsolete and RoHS non-compliant. Functionally and mechanically, they are identical.

Q: Can the 977-025-020R121 be used in applications originally designed for the 977-025-020-121?

A: Yes. The substitute part maintains full compatibility across all electrical and mechanical parameters. The improved RoHS compliance and MSL rating of the substitute part present no compatibility issues for existing applications.

Q: What packaging options are available for the substitute part?

A: The 977-025-020R121 is supplied in bulk packaging with 17,919 pieces available in current inventory.

Q: Are there any compatibility restrictions with D-Sub connector sizes?

A: Both parts are compatible with 25pos and HD44pos D-Sub sizes with shell size B. No restrictions apply to standard D-Sub 25-position or HD 44-position connector applications.