TTC-8122 Equivalent & Substitute Parts Reference

Part Overview

The TTC-8122 is a LAN 10 Base-T pulse transformer manufactured by Tamura, designed for 10BASE-T network applications. This component features a 19µH inductance with 1CT:1CT turns ratio configuration and is packaged in a 16-SOIC surface mount format. The part is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support and new design implementations where legacy compatibility is required.

Substiute Parts

TTC-8122

TamuraIn Stock: 1110TTC-8122 Datasheet

Current PartRFQ

PE-68786NL

Pulse ElectronicsIn Stock: 912PE-68786NL Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the TTC-8122 is determined by the following critical parameters:

Primary Substitution Criteria:

• Transformer Type classification (LAN 10 Base-T or compatible telecom pulse transformer)
• Inductance value (19µH primary specification)
• Turns Ratio configuration (1CT:1CT primary requirement)
• Mounting Type (Surface Mount compatibility)
• Physical dimensions and height constraints for PCB layout compatibility
• Moisture Sensitivity Level rating

Secondary Compatibility Factors:

• ECCN and HTSUS classifications (regulatory alignment)
• Operating temperature range
• RoHS and REACH compliance status

The PE-68786NL from Pulse Electronics is identified as a substitute part based on shared surface mount packaging, compatible physical dimensions within acceptable tolerance ranges, and equivalent ECCN classification. However, critical parameter differences exist that must be evaluated for specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

For Direct Functional Replacement:

The PE-68786NL cannot serve as a direct functional equivalent to the TTC-8122 due to fundamental differences in transformer specifications. The inductance value differs by a factor of 52.6 (1mH versus 19µH), and the turns ratio configuration differs (1CT:1.41CT versus 1CT:1CT). These parameters directly affect impedance matching, signal attenuation, and frequency response characteristics specific to 10BASE-T LAN applications versus T1/E1 telecom applications.

For Obsolescence Mitigation:

If the TTC-8122 is no longer available and functional replacement is required, the following factors must be evaluated:

1. Application Protocol Verification: Confirm whether the target system operates in 10BASE-T LAN environment or can accommodate T1/E1 telecom transformer characteristics.

2. Electrical Circuit Analysis: Conduct detailed circuit simulation to determine whether the 52.6x inductance increase and modified turns ratio are compatible with existing impedance matching networks and signal conditioning circuits.

3. Physical Integration: Verify that the 4.8% length increase, 2.9% width increase, and 2.1% height increase of the PE-68786NL do not violate PCB layout constraints or component clearance requirements.

4. Compliance Alignment: Both parts share EAR99 classification. The PE-68786NL provides active RoHS3 compliance and defined operating temperature range (0°C ~ 70°C), whereas the TTC-8122 specifications do not include these parameters.

5. Supply Chain Continuity: The PE-68786NL maintains active product status with documented inventory availability, providing supply chain stability compared to the obsolete TTC-8122.

Recommended Action Path:

Consult original equipment design documentation and circuit schematics to identify alternative LAN 10 Base-T pulse transformers with matching or compatible inductance (19µH ±tolerance) and turns ratio (1CT:1CT) specifications from active manufacturers. The PE-68786NL is suitable only if circuit redesign and protocol adaptation are feasible.

Frequently Asked Questions (FAQ)

Q: Can the PE-68786NL directly replace the TTC-8122 in existing 10BASE-T LAN circuits?

A: No. The PE-68786NL is designed for T1/E1 telecom applications and has fundamentally different electrical specifications (1mH inductance versus 19µH, and 1CT:1.41CT turns ratio versus 1CT:1CT). Direct substitution without circuit redesign will result in incorrect impedance matching and signal integrity failure in 10BASE-T applications.

Q: What are the critical parameters that determine substitution compatibility?

A: Substitution compatibility is determined by: (1) Transformer Type classification, (2) Inductance value, (3) Turns Ratio configuration, (4) Mounting Type, (5) Physical dimensions and height, and (6) Moisture Sensitivity Level. All parameters must align with the original circuit design specifications.

Q: Why is the TTC-8122 classified as obsolete?

A: The TTC-8122 is no longer manufactured by Tamura. Obsolete classification indicates end-of-life status and unavailability from primary distribution channels. Existing inventory may be available through secondary markets, but long-term supply cannot be guaranteed.

Q: What is the significance of the MSL rating difference between TTC-8122 (MSL 1) and PE-68786NL (MSL 3)?

A: MSL 1 (Unlimited) indicates the TTC-8122 has no moisture sensitivity restrictions and can be stored indefinitely without special environmental controls. MSL 3 (168 Hours) requires the PE-68786NL to be stored in controlled humidity environments and limits shelf life to 168 hours after moisture exposure. This affects component handling, storage, and manufacturing processes.

Q: Are the physical dimension differences between TTC-8122 and PE-68786NL significant?

A: The PE-68786NL is 4.8% longer (0.505" vs 0.457"), 2.9% wider (0.280" vs 0.272"), and 2.1% taller (0.245" vs 0.230"). These differences are within typical PCB layout tolerances but must be verified against specific board design constraints, component spacing requirements, and clearance specifications for the target application.

Q: What compliance certifications apply to each part?

A: Both parts share EAR99 export classification. The PE-68786NL provides documented RoHS3 compliance and REACH Unaffected status. The TTC-8122 compliance specifications are not provided in available documentation. For new designs, the PE-68786NL's active RoHS3 certification may be required for regulatory compliance.

Q: How should I proceed if I need to replace an obsolete TTC-8122?

A: (1) Verify the exact application requirements (10BASE-T LAN protocol and circuit specifications). (2) Search for active LAN 10 Base-T pulse transformers with matching inductance (19µH) and turns ratio (1CT:1CT) from current manufacturers. (3) If no direct equivalent exists, conduct detailed circuit analysis to determine whether alternative transformer specifications can be accommodated through impedance matching network redesign. (4) Consult with the original equipment manufacturer or design engineer for guidance on approved alternatives.