RNF12FTC249K Equivalent & Substitute Parts

Part Overview

The RNF12FTC249K is a 249 kOhms ±1% 0.5W 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 in compact axial packages. The part is currently active in production with ROHS3 compliance. Equivalent and substitute parts are identified to support procurement flexibility, inventory management, and supply chain continuity.

Substiute Parts

RNF12FTC249K

Stackpole Electronics IncIn Stock: 1169RNF12FTC249K Datasheet

Current PartRFQ

CMF55249K00FHEB

Vishay DaleIn Stock: 4512CMF55249K00FHEB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the RNF12FTC249K are qualified based on the following electrical and mechanical parameters:

• Resistance value: 249 kOhms (exact match required)
• Tolerance: ±1% (exact match required)
• Power rating: 0.5W / 1/2W (exact match required)
• Composition: Metal Film (exact match required)
• Package: Axial through-hole (exact match required)
• Temperature coefficient: ±50ppm/°C (exact match required)
• Compliance: ROHS3 Compliant (minimum requirement)

The CMF55249K00FHEB from Vishay Dale meets all electrical specifications and compliance requirements. Physical dimensions differ slightly, and the substitute offers extended operating temperature range and moisture resistance features.

Parameter Comparison

Engineering Selection Recommendations

Both the RNF12FTC249K and CMF55249K00FHEB are active production parts with ROHS3 compliance and REACH unaffected status. Selection between these parts is based on application-specific requirements:

The RNF12FTC249K is suitable for standard applications within the -55°C to 155°C operating range with standard moisture protection requirements.

The CMF55249K00FHEB is suitable for applications requiring extended temperature operation up to 175°C or enhanced moisture resistance. The smaller physical dimensions of the CMF55249K00FHEB may provide advantages in space-constrained PCB layouts, though board-level clearance verification is necessary.

Both parts carry identical electrical specifications (249 kOhms ±1%, 0.5W, ±50ppm/°C) and meet the same compliance standards, ensuring functional interchangeability within their respective operating parameters.

Frequently Asked Questions (FAQ)

Q: Can CMF55249K00FHEB replace RNF12FTC249K in all applications?

A: Yes, provided the application operates within the CMF55249K00FHEB's operating temperature range (-55°C to 175°C) and PCB layout accommodates the smaller physical dimensions (0.090" Dia x 0.240" L versus 0.108" Dia x 0.344" L).

Q: What are the key differences between these parts?

A: The primary differences are physical size, maximum operating temperature (175°C versus 155°C), and moisture resistance features. Electrical specifications are identical.

Q: Are both parts ROHS3 compliant?

A: Yes, both RNF12FTC249K and CMF55249K00FHEB are ROHS3 compliant and REACH unaffected.

Q: Does the smaller size of CMF55249K00FHEB affect performance?

A: No. The smaller dimensions do not affect electrical performance. Both parts maintain identical resistance, tolerance, power rating, and temperature coefficient specifications.

Q: What is the temperature coefficient significance?

A: Both parts have a temperature coefficient of ±50ppm/°C, meaning resistance changes by a maximum of 50 parts per million for each degree Celsius change in operating temperature. This specification is identical for both parts.

Q: Can these parts be used interchangeably on existing PCBs?

A: Physical dimensions differ. PCB layout verification is required to confirm that the smaller CMF55249K00FHEB fits within existing component footprints and clearance requirements.