RNF12FTC1K21 Equivalent & Substitute Parts

Part Overview

The RNF12FTC1K21 is a 1.21 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 with tight tolerance specifications. The part is currently in active production status with 1052 units available in inventory. Substitute parts are identified when equivalent electrical specifications and mechanical compatibility can be maintained across alternative manufacturers while preserving functional performance in target applications.

Substiute Parts

RNF12FTC1K21

Stackpole Electronics IncIn Stock: 1082RNF12FTC1K21 Datasheet

Current PartRFQ

CMF551K2100FHEB

Vishay DaleIn Stock: 9227CMF551K2100FHEB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the RNF12FTC1K21 are qualified based on the following critical parameters that determine functional equivalence:

• Resistance value: 1.21 kOhms (exact match required)
• Tolerance: ±1% (maintains precision specifications)
• Power rating: 0.5W / 1/2W (electrical stress capability)
• Composition: Metal Film (performance characteristics)
• Package: Axial (mechanical fit and PCB compatibility)
• Temperature coefficient: ±50ppm/°C (stability characteristics)
• Regulatory compliance: ROHS3 Compliant, REACH Unaffected

The CMF551K2100FHEB from Vishay Dale meets all these core electrical and mechanical requirements, enabling direct substitution in applications where the RNF12FTC1K21 is specified.

Parameter Comparison

Engineering Selection Recommendations

Both the RNF12FTC1K21 and CMF551K2100FHEB are active production components with ROHS3 compliance and REACH unaffected status, meeting current regulatory requirements for electronic component manufacturing and use.

The CMF551K2100FHEB provides an extended operating temperature range (-55°C ~ 175°C versus -55°C ~ 155°C) and includes moisture resistant features in addition to flame retardant coating. These characteristics may provide enhanced performance margins in applications subject to thermal cycling or humid environments.

Physical dimension differences exist between the two parts. The CMF551K2100FHEB is smaller in both diameter and length, which may affect PCB layout considerations and mechanical clearance requirements in space-constrained applications.

Selection between these parts should be based on specific application requirements regarding temperature range, environmental exposure, and available PCB space.

Frequently Asked Questions (FAQ)

Q: Can the CMF551K2100FHEB directly replace the RNF12FTC1K21 in all applications?

A: Both parts share identical electrical specifications (1.21 kOhms ±1%, 0.5W, ±50ppm/°C, metal film construction). Direct substitution is electrically valid. Physical dimensions differ, requiring verification of PCB layout compatibility and mechanical clearance.

Q: What is the significance of the moisture resistant feature in the CMF551K2100FHEB?

A: The moisture resistant feature provides additional protection against environmental moisture ingress. This is a supplementary characteristic beyond the flame retardant coating present in both parts and does not affect electrical equivalence.

Q: How do the operating temperature ranges differ between these parts?

A: The RNF12FTC1K21 operates from -55°C to 155°C, while the CMF551K2100FHEB operates from -55°C to 175°C. The CMF551K2100FHEB provides a 20°C higher upper temperature limit, offering extended thermal capability for high-temperature applications.

Q: Are there packaging format differences that affect component procurement?

A: The RNF12FTC1K21 is supplied in Tape & Reel (TR) format, while the CMF551K2100FHEB is supplied in Cut Tape (CT) format. These packaging differences affect handling, storage, and automated assembly processes but do not impact electrical or mechanical performance.

Q: Do both parts meet current regulatory compliance standards?

A: Both parts are ROHS3 compliant and REACH unaffected, meeting current regulatory requirements for electronic component use in regulated markets.