QFSS-078-04.25-L-D Equivalent & Substitute Parts

Part Overview

The QFSS-078-04.25-L-D is a 156-position rectangular connector receptacle manufactured by Samtec Inc. as part of the Q2™ QFSS series. This surface mount connector features center strip contacts with shielding and gold plating, designed for high-density interconnect applications requiring board-level connectivity. The part maintains Active product status with full RoHS3 compliance and unlimited moisture sensitivity rating (MSL 1). Substitute parts are identified when equivalent electrical and mechanical parameters are maintained across the same connector family, ensuring functional interchangeability in circuit board designs.

Substiute Parts

QFSS-078-04.25-L-D

Samtec Inc.In Stock: 1126QFSS-078-04.25-L-D Datasheet

Current PartRFQ

QFSS-078-04.25-L-D-A

Samtec Inc.In Stock: 1048QFSS-078-04.25-L-D-A Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the QFSS-078-04.25-L-D is determined by strict equivalence across the following critical parameters:

• Connector series and base product number (QFSS-078)
• Position count and row configuration (156 positions, 2 rows)
• Contact pitch and spacing (0.025" / 0.64mm)
• Mounting technology (Surface Mount)
• Contact material and finish specifications (Gold, 10.0µin thickness)
• Mechanical features (Board Guide, Ground Bus, Shielded)
• Physical dimensions (11mm stacking height, 0.278" above board)
• Compliance certifications (RoHS3, MSL 1)

Parts meeting all these parameters are classified as parametric equivalents and direct substitutes. Variations in packaging format (Tray) do not affect functional interchangeability.

Parameter Comparison

Engineering Selection Recommendations

Both the QFSS-078-04.25-L-D and QFSS-078-04.25-L-D-A maintain Active product status with identical compliance certifications. Selection between these parts should be based on inventory availability and supply chain requirements, as all electrical and mechanical specifications are equivalent. Both parts satisfy RoHS3 compliance requirements and carry MSL 1 rating, indicating no moisture sensitivity constraints during storage or handling. The suffix designation (-A) in the substitute part number reflects a manufacturing or packaging variant within the same product family, with no impact on functional performance or circuit board integration.

Frequently Asked Questions (FAQ)

Q: Can QFSS-078-04.25-L-D-A be used as a direct replacement for QFSS-078-04.25-L-D?

A: Yes. Both parts are parametric equivalents with identical electrical and mechanical specifications, including position count, pitch, contact finish, mounting type, and physical dimensions. They are functionally interchangeable in circuit board designs.

Q: What does the -A suffix in the substitute part number indicate?

A: The -A suffix represents a variant designation within the QFSS-078 base product family. This designation does not affect electrical performance, mechanical compatibility, or compliance certifications.

Q: Are there any differences in contact reliability or signal integrity between these parts?

A: No. Both parts feature identical contact material (gold), finish thickness (10.0µin), and shielding configuration. Signal integrity and contact reliability specifications are equivalent.

Q: Can these connectors be mixed in the same assembly?

A: Yes. Since both parts meet identical specifications for pitch, position count, mounting type, and physical dimensions, they can be used interchangeably within the same circuit board assembly without design modifications.

Q: What is the significance of the MSL 1 rating?

A: MSL 1 indicates unlimited moisture sensitivity, meaning these connectors require no special moisture control during storage, handling, or assembly. Standard warehouse and manufacturing conditions are acceptable.

Q: Are both parts RoHS3 compliant?

A: Yes. Both QFSS-078-04.25-L-D and QFSS-078-04.25-L-D-A carry full RoHS3 compliance certification, meeting all restricted substance requirements.