RNF14FAC665K Equivalent & Substitute Parts

Part Overview

The RNF14FAC665K is a 665 kOhms ±1% metal film axial resistor rated at 0.25W (1/4W) manufactured by Stackpole Electronics Inc. This through-hole component features flame retardant coating and safety-grade construction, designed for applications requiring precision resistance values with reliable performance across industrial temperature ranges. The part is currently in active production status with robust inventory availability. Substitute parts are identified to provide alternative sourcing options while maintaining electrical and mechanical compatibility within specified tolerance parameters.

Substiute Parts

RNF14FAC665K

Stackpole Electronics IncIn Stock: 1170RNF14FAC665K Datasheet

Current PartRFQ

CMF55665K00FHEB

Vishay DaleIn Stock: 1328CMF55665K00FHEB Datasheet

UpgradeRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the RNF14FAC665K are qualified based on the following electrical and mechanical parameters:

Critical Matching Parameters:

• Resistance value: 665 kOhms (exact match required)
• Tolerance: ±1% (maintains precision specification)
• Composition: Metal Film (ensures electrical characteristics)
• Temperature Coefficient: ±50ppm/°C (preserves stability performance)
• Package: Axial (maintains mechanical compatibility)
• Compliance: ROHS3 Compliant, REACH Unaffected (regulatory alignment)

Allowable Variation Parameters:

• Power Rating: Substitutes may exceed the 0.25W specification (0.5W acceptable as upgrade)
• Operating Temperature Range: Substitutes may extend the upper limit beyond 155°C
• Physical Dimensions: Minor variations within axial package standards
• Packaging Format: Tape & Box (TB) or Cut Tape (CT) formats are interchangeable

The CMF55665K00FHEB qualifies as a direct substitute based on matching all critical parameters while providing enhanced power rating and extended temperature range.

Parameter Comparison

Engineering Selection Recommendations

The CMF55665K00FHEB serves as a qualified substitute for the RNF14FAC665K in applications where the following conditions are met:

Direct Substitution Conditions:

• Electrical specifications require 665 kOhms ±1% resistance value
• Metal film composition is required for circuit performance
• Axial package format is mandated by PCB layout or mechanical constraints
• ROHS3 compliance and REACH compliance are regulatory requirements

Upgrade Considerations: The CMF55665K00FHEB provides enhanced specifications through increased power rating (0.5W versus 0.25W) and extended operating temperature range (-55°C ~ 175°C versus -55°C ~ 155°C). These upgrades do not compromise compatibility and may provide additional design margin in thermal or power dissipation scenarios. The addition of moisture-resistant features in the substitute part offers enhanced environmental protection without affecting electrical performance.

Compliance Verification: Both parts maintain ROHS3 compliance and REACH unaffected status, ensuring regulatory alignment for industrial and commercial applications.

Frequently Asked Questions (FAQ)

Q: Can the CMF55665K00FHEB replace the RNF14FAC665K in any application?

A: The CMF55665K00FHEB qualifies as a substitute when the circuit requires 665 kOhms ±1% resistance with metal film composition and axial package format. The higher power rating (0.5W) and extended temperature range do not create compatibility issues and are backward compatible with designs specified for the RNF14FAC665K.

Q: What is the significance of the power rating difference (0.25W vs 0.5W)?

A: The power rating indicates the maximum power dissipation the resistor can safely handle. The CMF55665K00FHEB's 0.5W rating provides greater thermal capacity than the RNF14FAC665K's 0.25W rating. In applications where the RNF14FAC665K operates within its 0.25W limit, the substitute will operate with additional thermal margin, which does not negatively affect performance.

Q: Are the physical dimensions compatible for PCB mounting?

A: Both parts use axial package format with similar dimensions (RNF14FAC665K: 0.093" Dia x 0.250" L; CMF55665K00FHEB: 0.090" Dia x 0.240" L). The minor dimensional differences remain within standard axial package tolerances and do not affect through-hole PCB mounting compatibility.

Q: What does the extended operating temperature range mean for the substitute part?

A: The CMF55665K00FHEB operates reliably from -55°C to 175°C, compared to the RNF14FAC665K's -55°C to 155°C range. This extended upper temperature limit provides additional operational margin in high-temperature environments without affecting performance in standard temperature applications.

Q: Are packaging format differences (Tape & Box vs Cut Tape) significant for substitution?

A: Packaging format differences relate to supply and handling methods only. Tape & Box (TB) and Cut Tape (CT) formats contain identical components and are functionally interchangeable. Format selection depends on assembly process requirements and inventory management practices.

Q: How does the moisture-resistant feature in the substitute part affect compatibility?

A: The moisture-resistant feature in the CMF55665K00FHEB provides enhanced environmental protection without altering electrical performance or mechanical compatibility. This feature is additive and does not create incompatibility with designs specified for the standard RNF14FAC665K.