ROX1SF650R Equivalent & Substitute Parts

Part Overview

The ROX1SF650R is a 650 Ohm ±1% 1W through-hole axial resistor manufactured by TE Connectivity Passive Product. This component features metal oxide film construction with flame-proof and pulse-withstanding characteristics, designed for safety-critical applications. The product is classified as obsolete, necessitating identification of equivalent substitute components that maintain functional compatibility while meeting current availability and compliance requirements.

Substiute Parts

ROX1SF650R

TE Connectivity Passive ProductIn Stock: 813ROX1SF650R Datasheet

Current PartRFQ

CMF55650R00FKEB

Vishay DaleIn Stock: 1029CMF55650R00FKEB Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ROX1SF650R is determined by the following critical parameters:

Mandatory Matching Parameters:

• Resistance value: 650 Ohms
• Tolerance: ±1%
• Package configuration: Axial through-hole
• Number of terminations: 2
• Safety classification: Safety-rated component

Allowable Variation Parameters:

• Power rating: Substitute must equal or exceed 1W requirement
• Composition: Metal film or metal oxide film acceptable
• Temperature coefficient: Substitute specifications must be documented
• Operating temperature range: Substitute must cover or exceed -55°C ~ 130°C range
• Product status: Active status preferred for long-term availability

The CMF55650R00FKEB from Vishay Dale meets the mandatory matching parameters with identical resistance, tolerance, and axial package configuration. However, the substitute features a reduced power rating of 0.5W, which represents a functional limitation in applications requiring full 1W dissipation capacity.

Parameter Comparison

Engineering Selection Recommendations

CMF55650R00FKEB Substitution Criteria:

The CMF55650R00FKEB is suitable as a substitute for the ROX1SF650R in applications where the following conditions are met:

1. Power Dissipation Requirement: The circuit design must accommodate a maximum power dissipation of 0.5W. Applications requiring full 1W dissipation capacity cannot use this substitute without circuit redesign.

2. Product Status and Availability: The CMF55650R00FKEB holds active product status with documented inventory availability, addressing the obsolescence limitation of the ROX1SF650R.

3. Compliance and Certification: The CMF55650R00FKEB carries RoHS3 compliance and REACH affected status, meeting current regulatory requirements. Both components share identical ECCN (EAR99) and HTSUS (8533.21.0090) classifications.

4. Thermal Performance: The substitute provides an extended operating temperature range (-55°C ~ 175°C) and improved temperature coefficient (±100ppm/°C), offering enhanced thermal stability compared to the original component.

5. Physical Footprint: The substitute features reduced physical dimensions (0.090" Dia x 0.240" L versus 0.138" Dia x 0.394" L), which may require PCB layout verification for mechanical compatibility.

6. Safety Features: Both components maintain safety-rated classifications with appropriate flame protection characteristics suitable for safety-critical applications.

Frequently Asked Questions (FAQ)

Q: Can the CMF55650R00FKEB directly replace the ROX1SF650R in all applications?

A: Direct replacement is limited by power rating. The substitute is rated for 0.5W maximum dissipation, while the original component is rated for 1W. Substitution is valid only in circuits where actual power dissipation does not exceed 0.5W.

Q: What is the significance of the different composition types (Metal Oxide Film vs. Metal Film)?

A: The ROX1SF650R uses metal oxide film construction, while the CMF55650R00FKEB uses metal film construction. Both compositions meet the specified resistance, tolerance, and safety requirements. Metal film construction in the substitute provides superior temperature coefficient performance (±100ppm/°C versus ±350ppm/°C).

Q: Are there physical compatibility concerns with the smaller substitute component?

A: Yes. The CMF55650R00FKEB has significantly reduced dimensions (0.090" Dia x 0.240" L) compared to the ROX1SF650R (0.138" Dia x 0.394" L). PCB layout and mechanical mounting must be verified to ensure the smaller component fits within the available space and maintains proper lead spacing.

Q: Does the extended operating temperature range of the substitute provide additional benefits?

A: The CMF55650R00FKEB operates across -55°C ~ 175°C, exceeding the ROX1SF650R range of -55°C ~ 130°C. This extended range provides design margin for applications operating at elevated temperatures, though the original specification range is maintained.

Q: What compliance advantages does the substitute offer?

A: The CMF55650R00FKEB carries active RoHS3 compliance and documented REACH affected status, meeting current regulatory requirements. The obsolete ROX1SF650R does not carry current compliance certifications, making the substitute preferable for new designs and long-term supply chain management.

Q: How do the packaging formats differ between these components?

A: The ROX1SF650R is supplied in standard packaging format, while the CMF55650R00FKEB is supplied in Tape & Reel (TR) format. This difference affects procurement quantities and automated assembly compatibility but does not impact electrical performance.

Q: Is the ±1% tolerance specification maintained in the substitute?

A: Yes. Both the ROX1SF650R and CMF55650R00FKEB maintain ±1% tolerance on the 650 Ohm resistance value, ensuring equivalent accuracy for precision circuit applications.