Molex 2138672833 NTC Thermistor Ring Lug - Equivalent & Substitute Parts

Part Overview

The Molex 2138672833 is an NTC thermistor with a 20kΩ resistance at 25°C, configured as a ring lug connector for temperature sensing applications. This component features a 75mm lead wire length and operates across a -40°C to 150°C temperature range. The part is classified as obsolete, making identification of suitable substitutes essential for ongoing procurement and system maintenance.

Substiute Parts

2138672833

MolexIn Stock: 6952138672833 Datasheet

Current PartRFQ

2138652833

MolexIn Stock: 17702138652833 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for NTC thermistor ring lugs is determined by the following parameters:

• Resistance Value @ 25°C: Must match at 20kΩ
• Resistance Tolerance: Must be ±2% or tighter
• Lead Wire Length: Must match at 75mm
• Package / Case Type: Must be Ring Lug configuration
• Mounting Type: Must be Free Hanging
• RoHS Compliance: Must maintain ROHS3 Compliant status

The Molex 2138652833 meets all substitution criteria. While the B25/85 value differs (3982K vs. 4020K) and the maximum operating temperature is lower (-40°C ~ 105°C vs. -40°C ~ 150°C), the core electrical parameters and physical form factor remain compatible for applications within the substitute's operating range.

Parameter Comparison

Engineering Selection Recommendations

The Molex 2138652833 is the qualified substitute for the obsolete 2138672833. Both components maintain ROHS3 compliance and identical core electrical specifications at 25°C. The substitute is currently in active production status with higher inventory availability (1702 pcs vs. 657 pcs).

Selection of the substitute requires verification that the application's maximum operating temperature does not exceed 105°C, as this represents the primary functional difference between the two parts. The substitute's higher maximum power rating (150 mW vs. 100 mW) provides additional thermal margin in most applications.

Frequently Asked Questions (FAQ)

Q: Can the 2138652833 directly replace the 2138672833 in all applications?

A: Direct replacement is valid only for applications where the maximum operating temperature remains below 105°C. The original part supports operation to 150°C; the substitute does not. Verify your system's thermal requirements before substitution.

Q: What is the significance of the B25/85 value difference (4020K vs. 3982K)?

A: The B25/85 value characterizes the thermistor's temperature coefficient. The 38K difference represents approximately 0.9% variation. This affects the resistance-temperature curve and may impact calibration accuracy in precision temperature measurement applications. Evaluate your system's tolerance requirements.

Q: Are both parts RoHS compliant?

A: Yes. Both the 2138672833 and 2138652833 are ROHS3 compliant, meeting current environmental and regulatory standards.

Q: Why is the original part obsolete?

A: The 2138672833 is classified as obsolete by Molex. The 2138652833 represents the active production alternative with equivalent core functionality and improved availability.

Q: Does the higher power rating of the substitute (150 mW vs. 100 mW) affect compatibility?

A: No. A higher power rating indicates the component can safely dissipate more thermal energy. This provides additional design margin and does not create compatibility issues in applications designed for the original 100 mW specification.