TE Connectivity 643821-3 Rectangular Connector Equivalent & Substitute Parts

Part Overview

The TE Connectivity 643821-3 is a 3-position rectangular receptacle connector from the MTA-156 series, designed for IDC (Insulation Displacement Contact) termination with 26 AWG discrete or ribbon cable. This connector features a tin-lead contact finish, closed-end design, and polarizing key for secure mating.

The 643821-3 is classified as obsolete. Locating equivalent substitute parts is necessary to support ongoing maintenance, repair, and production requirements for legacy systems utilizing this connector configuration.

Substiute Parts

643821-3

TE Connectivity AMP ConnectorsIn Stock: 854643821-3 Datasheet

Current PartRFQ

3-643821-3

TE Connectivity AMP ConnectorsIn Stock: 12673-643821-3 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 643821-3 is determined by strict equivalence across the following critical parameters:

• Connector Type & Series: Must be MTA-156 series receptacle connector
• Position Count & Pitch: Must maintain 3 positions at 0.156" (3.96mm) pitch
• Termination Method: Must support IDC cable termination
• Wire Gauge Compatibility: Must accommodate 26 AWG wire
• Contact Configuration: Must feature female socket contacts with identical finish thickness
• Mechanical Features: Must include closed-end design and polarizing key
• Mounting Orientation: Must be free hanging in-line configuration

The substitute part 3-643821-3 meets all these criteria and is therefore classified as a direct equivalent.

Parameter Comparison

Engineering Selection Recommendations

The 643821-3 is an obsolete part with tin-lead contact finish and RoHS non-compliant status. The direct substitute 3-643821-3 provides functional equivalence across all critical electrical and mechanical parameters while offering the following advantages:

Active Product Status: The 3-643821-3 is classified as active, ensuring continued availability and supply chain support for future procurement requirements.

RoHS Compliance: The 3-643821-3 meets RoHS compliance standards, making it suitable for applications subject to environmental and regulatory restrictions on hazardous substances.

Contact Finish Upgrade: The 3-643821-3 features pure tin contact finish in place of tin-lead, providing improved environmental compatibility while maintaining the specified contact finish thickness of 80.0µin (2.03µm).

Mechanical & Electrical Equivalence: All connector specifications—pitch, position count, IDC termination, wire gauge compatibility, mounting configuration, and polarizing features—remain identical between the main part and substitute.

For applications where tin-lead contact finish is specifically required, the 643821-3 remains the only option; however, the 3-643821-3 is the recommended selection for new designs and ongoing production where regulatory compliance and supply continuity are priorities.

Frequently Asked Questions (FAQ)

Q: Can the 3-643821-3 be used as a direct replacement for the 643821-3 in existing assemblies?

A: Yes. The 3-643821-3 is mechanically and electrically equivalent to the 643821-3. Both connectors share identical pitch (0.156"), position count (3), IDC termination method, 26 AWG wire gauge compatibility, mounting type, and polarizing features. Mating with corresponding plug connectors and cable assemblies designed for the 643821-3 will function identically with the 3-643821-3.

Q: What is the difference between the tin-lead finish on the 643821-3 and the tin finish on the 3-643821-3?

A: The 643821-3 uses tin-lead contact plating, while the 3-643821-3 uses pure tin plating. Both maintain the same contact finish thickness of 80.0µin (2.03µm). The tin finish on the 3-643821-3 eliminates lead content, making it compliant with RoHS regulations and suitable for applications with environmental restrictions.

Q: Why is the 643821-3 listed as obsolete?

A: The 643821-3 has been discontinued by TE Connectivity. The 3-643821-3 represents the active product line continuation, offering the same connector functionality with updated compliance standards and materials.

Q: Are there packaging differences between the 643821-3 and 3-643821-3?

A: The 643821-3 packaging is not specified in available documentation. The 3-643821-3 is supplied in bulk packaging. Confirm packaging requirements with your procurement or supply chain department when ordering.

Q: What is the REACH and RoHS status of these connectors?

A: The 643821-3 is RoHS non-compliant and REACH Affected. The 3-643821-3 is RoHS Compliant with REACH status listed as Vendor Undefined. For applications requiring specific REACH compliance documentation, contact TE Connectivity directly.

Q: Can I use these connectors with both discrete and ribbon cable?

A: Yes. Both the 643821-3 and 3-643821-3 support IDC termination with discrete or ribbon cable at 26 AWG wire gauge. The IDC termination method allows direct insertion of wire without pre-stripping.

Q: What is the moisture sensitivity level (MSL) for these connectors?

A: Both connectors have an MSL rating of 1 (Unlimited), indicating no moisture sensitivity restrictions for storage or handling.