L77DB25SC – 25 Position D-Sub Receptacle, Right Angle Solder

Part Overview

The L77DB25SC is a 25 position D-Sub receptacle connector manufactured by Amphenol ICC (Commercial Products). This through-hole, right-angle solder termination connector features female sockets in a DB-3 shell configuration. The part is currently in active production status with 1043 units in stock.

Substitute parts become necessary when the primary part is unavailable, when design requirements shift, or when supply chain optimization requires sourcing from alternative manufacturers while maintaining electrical and mechanical compatibility.

Substiute Parts

L77DB25SC

Amphenol ICC (Commercial Products)In Stock: 1103L77DB25SC Datasheet

Current PartRFQ

174-025-212R141

NorComp Inc.In Stock: 1186174-025-212R141 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution compatibility for the L77DB25SC is determined by strict adherence to the following critical parameters:

Mandatory Matching Parameters:

• Connector type: D-Sub receptacle with female sockets
• Number of positions: 25
• Number of rows: 2
• Shell size: 3 (DB, B)
• Mounting type: Through hole, right angle orientation
• Termination method: Solder
• Contact material: Brass with gold finish
• Contact form: Machined

Allowable Variation Parameters:

• Shell material finish (tin or alternative plating)
• Contact finish thickness (within gold plating specifications)
• Dielectric material (thermoplastic variations)
• Flange feature design (housing style differences)
• Operating temperature range (substitute must support required application range)
• Current rating (substitute must equal or exceed requirement)
• Voltage rating (substitute must equal or exceed requirement)
• Backset spacing (minor tolerance variations acceptable within mechanical constraints)
• Color (cosmetic difference only)
• Product status (active or obsolete acceptable if electrically/mechanically equivalent)
• RoHS and compliance certifications (equivalent or superior status)

The identified substitute part 174-025-212R141 meets the mandatory matching parameters while demonstrating acceptable variations in allowed categories.

Parameter Comparison

Engineering Selection Recommendations

L77DB25SC (Primary Part): The L77DB25SC is the recommended primary selection. This part maintains active production status, ensuring reliable long-term availability and supply chain support. It is RoHS compliant and carries a current rating of 7.5A with full temperature range operation from -55°C to 125°C, supporting applications across broad environmental conditions.

174-025-212R141 (Substitute Part): The 174-025-212R141 from NorComp Inc. serves as an electrical and mechanical substitute with the following engineering considerations:

The substitute maintains equivalent shell size, pin configuration, solder termination, and contact material specifications. However, the following differences require assessment:

• Current Rating: The substitute part is rated for 5A, which is lower than the main part's 7.5A rating. Use the substitute only in applications where the required current draw does not exceed 5A.
• Operating Temperature: The substitute supports -50°C to 100°C, which is narrower than the main part's -55°C to 125°C range. Verify application requirements fall within these limits.
• Backset Spacing: The substitute exhibits 0.370" (9.40mm) backset spacing compared to the main part's 0.319" (8.10mm). PCB layout and component spacing must accommodate this difference.
• Flange Design: The substitute features female screwlock (4-40) mating-side fastening, whereas the main part uses unthreaded housing. Mechanical mounting interfaces must be compatible.
• Dielectric Material: The substitute uses PBT polyester composition versus the main part's thermoplastic glass-filled material. Both maintain UL94 V-0 flammability certification.
• Product Status: The substitute is marked obsolete. Availability may be limited, requiring verification of current inventory and long-term supply viability before design commitment.

Both parts are ECCN EAR99 and HTSUS 8536.69.4040 classified.

Frequently Asked Questions (FAQ)

Q: Can the 174-025-212R141 be directly substituted for the L77DB25SC in all applications?

A: Direct substitution requires verification of application-specific requirements. The substitute is mechanically and electrically compatible for connector type, pin count, termination method, and contact material. However, confirm that application current requirements do not exceed 5A, operating temperature remains within -50°C to 100°C, and PCB layout tolerates the 0.051" (1.30mm) difference in backset spacing. The different flange design and mounting interface must be assessed for mechanical compatibility.

Q: What is the significance of the different backset spacing between these parts?

A: Backset spacing is the distance from the mating face of the connector to the center of the solder tail contact points. The 0.051" difference (8.10mm versus 9.40mm) affects PCB land pattern design and component placement. Parts with different backset spacing cannot be directly interchanged on the same PCB without layout modification.

Q: Why does the substitute part have a lower current rating?

A: Current rating depends on contact geometry, material composition, and thermal design. The 174-025-212R141 is rated for 5A maximum, reflecting its internal contact design specifications. Applications requiring higher current density must use the L77DB25SC or verify that actual circuit current requirements remain below the substitute's 5A limit.

Q: Is the 174-025-212R141 still available if it is marked obsolete?

A: Obsolete status indicates the manufacturer has discontinued production. However, inventory may exist through distributors or resellers. Availability is not guaranteed and may be limited. For new designs, the active L77DB25SC is the appropriate selection to ensure long-term supply chain stability.

Q: How do the dielectric materials compare in performance?

A: Both materials—thermoplastic glass-filled and PBT polyester—achieve UL94 V-0 flammability certification. The dielectric materials differ in composition but both support the voltage and environmental specifications of their respective connectors. Material selection should be evaluated based on application environmental exposure and mechanical stress requirements.

Q: What is the functional difference between the unthreaded housing flange and the female screwlock flange?

A: The unthreaded housing flange on the L77DB25SC requires mechanical fastening through the shell. The female screwlock (4-40) design on the 174-025-212R141 incorporates threaded mounting holes on the connector body itself. The mounting interface design is fundamentally different and requires compatible mechanical hardware on the installation surface.