TE Connectivity 643818-8 Rectangular Connector Equivalent & Substitute Parts

Part Overview

The TE Connectivity 643818-8 is an 8-position rectangular receptacle connector from the MTA-156 series, designed for IDC (Insulation Displacement Contact) termination with 20 AWG discrete or ribbon cable. This connector features a tin-lead contact finish, closed-end design with polarizing key, and free-hanging in-line mounting configuration. The part is currently active in production with 791 pieces in stock inventory.

Substitute parts are identified to address specific application requirements including RoHS compliance status, contact finish specifications, and packaging variations while maintaining electrical and mechanical compatibility.

Substiute Parts

643818-8

TE Connectivity AMP ConnectorsIn Stock: 861643818-8 Datasheet

Current PartRFQ

3-643818-8

TE Connectivity AMP ConnectorsIn Stock: 11973-643818-8 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The substitute part 3-643818-8 is classified as a direct equivalent based on the following matching parameters:

Electrical Compatibility Parameters:

• Connector type: Receptacle
• Number of positions: 8
• Pitch: 0.156" (3.96mm)
• Contact type: Female Socket
• Wire gauge: 20 AWG
• Cable termination: IDC

Mechanical Compatibility Parameters:

• Series: MTA-156
• Mounting type: Free Hanging (In-Line)
• Fastening type: Locking Ramp
• Features: Closed End, Polarizing Key
• Contact finish thickness: 80.0µin (2.03µm)

Distinguishing Characteristics: The primary difference between the main part and substitute is the contact finish specification (tin-lead versus tin) and RoHS compliance status. The substitute part 3-643818-8 features a tin contact finish and is RoHS compliant, whereas the main part 643818-8 features a tin-lead contact finish and is RoHS non-compliant. Both parts share identical mechanical dimensions, pitch, position count, and termination methodology.

Parameter Comparison

Engineering Selection Recommendations

For RoHS-Compliant Applications: Select part number 3-643818-8. This substitute provides full RoHS compliance while maintaining all electrical and mechanical specifications of the MTA-156 series. The tin contact finish eliminates lead content, meeting regulatory requirements for applications subject to RoHS directives.

For Legacy or Non-Regulated Applications: Either part 643818-8 or 3-643818-8 is acceptable. The tin-lead contact finish of 643818-8 may be preferred in applications where lead-based finishes are specified or where existing inventory compatibility is required.

Packaging Considerations: Part 3-643818-8 is supplied in bulk packaging with higher inventory availability (1173 pieces versus 791 pieces). This may be advantageous for high-volume production requirements.

Contact Finish Selection: Both tin-lead and tin finishes provide equivalent contact resistance and reliability characteristics at the specified 80.0µin (2.03µm) thickness. Selection between these finishes is determined by regulatory compliance requirements and application specifications rather than electrical performance.

Frequently Asked Questions (FAQ)

Q: Can 3-643818-8 be used as a direct replacement for 643818-8 in existing designs?

A: Yes. The parts are mechanically and electrically interchangeable. The primary difference is the contact finish (tin versus tin-lead) and RoHS compliance status. If the original design does not explicitly require tin-lead contact finish or non-compliant status, 3-643818-8 is a direct substitute.

Q: What is the significance of the contact finish difference between these parts?

A: The contact finish affects material composition and regulatory compliance. Tin-lead (643818-8) contains lead and is RoHS non-compliant. Tin (3-643818-8) is lead-free and RoHS compliant. Both finishes provide equivalent electrical performance at the specified thickness of 80.0µin (2.03µm).

Q: Are these connectors compatible with both discrete and ribbon cable?

A: Yes. Both parts support IDC termination for discrete or ribbon cable at 20 AWG wire gauge. The IDC termination method accommodates both cable types without modification.

Q: What does the polarizing key feature provide?

A: The polarizing key ensures correct connector orientation during mating, preventing reversed insertion and potential circuit damage or malfunction.

Q: Is the pitch specification critical for substitution?

A: Yes. The 0.156" (3.96mm) pitch is a critical parameter. Connectors with different pitch specifications are not interchangeable and will not mate correctly with existing mating connectors or PCB layouts.

Q: What is the difference between the base product number 643818 and the full part numbers?

A: The base product number 643818 identifies the connector family. The suffix "-8" indicates the 8-position configuration. Different suffixes would indicate different position counts within the same series.

Q: Can these connectors be used in applications requiring moisture resistance?

A: Both parts have Moisture Sensitivity Level (MSL) 1, indicating unlimited moisture resistance. No special moisture protection measures are required during storage or handling.