Amphenol ICC 51939-740 Backplane Connector - Equivalent & Substitute Parts

Part Overview

The Amphenol ICC 51939-740 is a 40-position blade power connector header designed for board edge, through-hole, right-angle mounting applications. This connector features male pins and blades with a 0.100" (2.54mm) pitch, organized in 4 rows with a typical contact layout of 28 signal and 12 power positions. The connector is part of the PwrBlade® series and utilizes gold or gold GXT™ contact finish with UL94 V-0 flammability rating.

The 51939-740 is currently listed as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production or maintenance requirements for systems utilizing this connector.

Substiute Parts

51939-740

Amphenol ICC (FCI)In Stock: 84051939-740 Datasheet

Current PartRFQ

51939-740LF

Amphenol ICC (FCI)In Stock: 88151939-740LF Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 51939-740 is determined by strict equivalence across the following critical parameters:

• Connector type and style (Header, Male Pins and Blades; Blade Power)
• Number of positions (40)
• Pitch specification (0.100" / 2.54mm)
• Row configuration (4 rows)
• Contact layout (28 Signal, 12 Power)
• Mounting type (Board Edge, Through Hole, Right Angle)
• Termination method (Solder)
• Contact finish specification (Gold or Gold, GXT™)
• Contact finish thickness (30.0µin / 0.76µm)
• Color (Black)
• Flammability rating (UL94 V-0)
• Operating temperature range (-20°C ~ 105°C)
• Series designation (PwrBlade®)

The substitute part 51939-740LF meets all these criteria and is therefore electrically and mechanically equivalent to the main part number.

Parameter Comparison

Engineering Selection Recommendations

The 51939-740LF is the direct equivalent substitute for the obsolete 51939-740. Both parts share identical electrical and mechanical specifications across all critical parameters including connector type, position count, pitch, mounting configuration, contact layout, and operating characteristics.

The primary distinction between these parts is product status and regulatory compliance. The 51939-740 is obsolete and RoHS non-compliant, while the 51939-740LF is active and RoHS compliant. The 51939-740LF is supplied in Tray packaging, whereas packaging information for the main part is not specified.

For new designs or ongoing production requiring compliance with current regulatory standards, the 51939-740LF is the appropriate selection. For legacy system maintenance where RoHS compliance is not a requirement, the 51939-740LF remains functionally equivalent and provides superior supply chain availability.

Frequently Asked Questions (FAQ)

Q: Are the 51939-740 and 51939-740LF electrically interchangeable?

A: Yes. Both connectors are electrically equivalent. They share identical specifications for connector type, number of positions (40), pitch (0.100"), contact layout (28 Signal, 12 Power), contact finish (Gold or Gold, GXT™), and operating temperature range (-20°C ~ 105°C).

Q: What is the difference between these two part numbers?

A: The primary differences are product status and regulatory compliance. The 51939-740 is obsolete and RoHS non-compliant. The 51939-740LF is active and RoHS compliant. The 51939-740LF is supplied in Tray packaging. All electrical and mechanical specifications are identical.

Q: Can I use the 51939-740LF as a direct replacement for the 51939-740 in existing designs?

A: Yes. The 51939-740LF is mechanically and electrically equivalent to the 51939-740. It will function identically in applications designed for the original part number. The improved RoHS compliance status of the 51939-740LF makes it the preferred choice for new procurement.

Q: What does the "LF" suffix in 51939-740LF indicate?

A: The "LF" suffix typically indicates lead-free or RoHS-compliant processing. The 51939-740LF is RoHS compliant, whereas the 51939-740 is RoHS non-compliant.

Q: Are there any packaging considerations when switching from 51939-740 to 51939-740LF?

A: The 51939-740LF is supplied in Tray packaging. If your assembly process requires a different packaging format, this should be confirmed with your supplier. The connector itself is identical regardless of packaging.

Q: What is the Moisture Sensitivity Level (MSL) for these connectors?

A: Both the 51939-740 and 51939-740LF have an MSL rating of 1 (Unlimited), indicating no moisture sensitivity restrictions for storage or handling.