RNF12FTC249R Equivalent & Substitute Parts

Part Overview

The RNF12FTC249R is a 249 Ohms ±1% 0.5W through-hole axial resistor manufactured by Stackpole Electronics Inc. This metal film resistor features flame retardant coating and safety characteristics, designed for applications requiring precision resistance values with stable performance across industrial temperature ranges. The part maintains Active product status with 724 units in current inventory. Substitute parts are identified to provide alternative sourcing options while maintaining electrical and mechanical compatibility within specified parameter tolerances.

Substiute Parts

RNF12FTC249R

Stackpole Electronics IncIn Stock: 826RNF12FTC249R Datasheet

Current PartRFQ

CMF55249R00FHEA

Vishay DaleIn Stock: 6472CMF55249R00FHEA Datasheet

MFR RecommendedRFQ

CMF55249R00FHEB

Vishay DaleIn Stock: 8328CMF55249R00FHEB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts CMF55249R00FHEA and CMF55249R00FHEB are qualified as equivalent alternatives based on the following matching criteria:

• Resistance value: 249 Ohms (identical)
• Tolerance: ±1% (identical)
• Power rating: 0.5W / 1/2W (identical)
• Composition: Metal Film (identical)
• Temperature coefficient: ±50ppm/°C (identical)
• Package type: Axial (identical)
• Number of terminations: 2 (identical)
• Compliance: ROHS3 Compliant, REACH Unaffected, EAR99 (identical)

Both substitute parts are manufactured by Vishay Dale and maintain the same electrical performance specifications. The substitutes provide additional moisture resistance features and extended operating temperature range (-55°C ~ 175°C) compared to the main part. Physical dimensions differ slightly, with substitute parts measuring 0.090" Dia x 0.240" L versus the main part's 0.108" Dia x 0.344" L.

Parameter Comparison

Engineering Selection Recommendations

All three parts maintain Active product status and ROHS3 compliance. The RNF12FTC249R and both CMF55 variants are electrically equivalent for applications requiring 249 Ohm ±1% metal film resistors at 0.5W power dissipation.

Selection between the main part and substitutes should consider:

• Physical space constraints: Substitute parts are smaller (0.090" Dia x 0.240" L) compared to the main part (0.108" Dia x 0.344" L), enabling use in compact layouts
• Temperature environment: Substitute parts support extended operating range to 175°C versus 155°C for the main part
• Moisture exposure: Substitute parts include moisture resistance features suitable for humid environments
• Packaging format: Main part supplied in Tape & Reel; substitutes supplied in Cut Tape format

Frequently Asked Questions (FAQ)

Q: Can CMF55249R00FHEA and CMF55249R00FHEB be used interchangeably with RNF12FTC249R?

A: Yes. Both substitute parts match the electrical specifications (249 Ohms ±1%, 0.5W, ±50ppm/°C) and maintain identical compliance certifications. Physical dimensions differ, requiring verification of PCB layout compatibility.

Q: What is the difference between CMF55249R00FHEA and CMF55249R00FHEB?

A: Both parts are electrically and mechanically identical. The difference lies in packaging batch designation (FHEA versus FHEB). Both are manufactured by Vishay Dale with identical specifications and performance characteristics.

Q: Are the smaller dimensions of the substitute parts a limitation?

A: The reduced size (0.090" Dia x 0.240" L) of CMF55 variants is an advantage for space-constrained designs. PCB layout and component spacing must accommodate the smaller form factor. Axial lead spacing and hole positioning remain compatible with standard 0.1" grid layouts.

Q: Do the substitute parts require any design changes?

A: No design changes are required for electrical function. Physical layout verification is necessary due to dimensional differences. All parts are axial through-hole components with identical lead termination count (2).

Q: What is the significance of the extended temperature range in substitute parts?

A: CMF55249R00FHEA and CMF55249R00FHEB support operation to 175°C versus 155°C for the RNF12FTC249R. This extended range provides margin for applications with elevated ambient or self-heating conditions, though both parts meet the same temperature coefficient specification (±50ppm/°C).