RNF14FAC40K2 Equivalent & Substitute Parts

Part Overview

The RNF14FAC40K2 is a 40.2 kOhms ±1% 0.25W (1/4W) through-hole axial resistor manufactured by Stackpole Electronics Inc. This metal film resistor features flame retardant coating and safety construction, designed for applications requiring precision resistance values with tight tolerance specifications. The part is currently active in production with 931 units in stock. Substitute parts are identified to provide alternative sourcing options while maintaining electrical and mechanical compatibility within specified parameters.

Substiute Parts

RNF14FAC40K2

Stackpole Electronics IncIn Stock: 1022RNF14FAC40K2 Datasheet

Current PartRFQ

CMF5540K200FHEB

Vishay DaleIn Stock: 1654CMF5540K200FHEB Datasheet

UpgradeRFQ

CMF5040K200FHEB

Vishay DaleIn Stock: 2329CMF5040K200FHEB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the RNF14FAC40K2 are qualified based on the following electrical and mechanical parameters:

Critical Parameters (Must Match):

• Resistance value: 40.2 kOhms
• Tolerance: ±1%
• Composition: Metal Film
• Package type: Axial
• Temperature coefficient: ±50ppm/°C
• RoHS compliance: ROHS3 Compliant

Allowable Variations:

• Power rating: May be equal or higher than 0.25W
• Operating temperature range: May be equal or extended
• Physical dimensions: May vary within axial package constraints
• Packaging format: Cut Tape (CT) or Tape & Box (TB)
• Manufacturer: Different qualified manufacturers permitted

Two substitute parts meet these criteria: CMF5040K200FHEB (manufacturer-recommended direct equivalent) and CMF5540K200FHEB (upgraded power rating variant).

Parameter Comparison

Engineering Selection Recommendations

CMF5040K200FHEB (Manufacturer-Recommended Equivalent): This part is the direct electrical equivalent to the RNF14FAC40K2, maintaining identical resistance, tolerance, power rating, and temperature coefficient specifications. The CMF5040K200FHEB offers extended operating temperature range (-55°C ~ 175°C versus -55°C ~ 155°C) and includes moisture-resistant features. Physical dimensions are smaller, which may provide layout advantages in space-constrained applications. Both parts are ROHS3 compliant and carry identical ECCN and HTSUS classifications. This part is recommended for direct substitution where packaging format (Cut Tape) is acceptable.

CMF5540K200FHEB (Upgraded Power Rating Variant): This part provides the same electrical specifications as the main part with an upgraded power rating of 0.5W (1/2W) versus 0.25W (1/4W). The higher power rating permits operation in applications with greater thermal dissipation requirements while maintaining all other critical parameters. Extended operating temperature range and moisture-resistant construction are included. Physical dimensions are comparable to the main part. This part is suitable for applications where increased power handling capability is beneficial or required.

Frequently Asked Questions (FAQ)

Q: Can CMF5040K200FHEB be used as a direct replacement for RNF14FAC40K2?

A: Yes. Both parts share identical electrical specifications: 40.2 kOhms ±1% resistance, ±50ppm/°C temperature coefficient, and 0.25W power rating. The CMF5040K200FHEB is classified as the manufacturer-recommended equivalent. The primary difference is packaging format (Cut Tape versus Tape & Box) and extended operating temperature range on the substitute part.

Q: What is the difference between CMF5040K200FHEB and CMF5540K200FHEB?

A: The primary difference is power rating. CMF5040K200FHEB is rated at 0.25W (1/4W), matching the original part. CMF5540K200FHEB is rated at 0.5W (1/2W), providing higher power dissipation capability. All other electrical parameters remain identical. Physical dimensions differ slightly due to the higher power rating.

Q: Are physical dimensions critical for substitution?

A: Physical dimensions should be evaluated based on circuit board layout constraints. The CMF5040K200FHEB is smaller (0.065" Dia x 0.150" L) than the original RNF14FAC40K2 (0.093" Dia x 0.250" L), which may provide layout advantages. The CMF5540K200FHEB dimensions (0.090" Dia x 0.240" L) are comparable to the original part. All three parts use axial package configuration and are mechanically compatible with standard through-hole mounting.

Q: Do all substitute parts meet the same compliance requirements?

A: Yes. All parts listed are ROHS3 compliant, REACH unaffected, and classified under identical ECCN (EAR99) and HTSUS (8533.21.0090) codes. Moisture sensitivity level is not applicable for all parts.

Q: What is the temperature coefficient specification and why does it matter?

A: All parts maintain ±50ppm/°C temperature coefficient, which defines the resistance change per degree Celsius within the operating temperature range. This specification is critical for precision applications requiring stable resistance values across temperature variations. The identical temperature coefficient across all parts ensures equivalent performance in temperature-sensitive circuits.