Ohmite 40F68R Equivalent & Substitute Parts

Part Overview

The Ohmite 40F68R is a 68 Ohm, 1% tolerance, 10W axial wirewound through-hole resistor from the Ohmicone® 40 series. This component is designed for applications requiring precision resistance with high power dissipation capability in a compact axial package. The part is currently active in production with 919 units in stock. Substitute parts are identified when original stock becomes unavailable or when specific packaging or compliance requirements necessitate alternative sourcing.

Substiute Parts

40F68R

OhmiteIn Stock: 98440F68R Datasheet

Current PartRFQ

40F68RE

OhmiteIn Stock: 110440F68RE Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 40F68R are identified based on electrical and mechanical parameter equivalence. The primary substitution criterion is parametric matching across the following key parameters:

• Resistance value: 68 Ohms
• Tolerance: ±1%
• Power rating: 10W
• Composition: Wirewound
• Package configuration: Axial
• Temperature coefficient: ±20ppm/°C
• Physical dimensions: 0.406" Dia x 1.902" L

The 40F68RE is classified as a parametric equivalent because it maintains identical electrical specifications and physical dimensions. Differences in packaging format (Bulk vs. standard) and RoHS compliance status do not affect functional interchangeability in circuit applications.

Parameter Comparison

Engineering Selection Recommendations

Both the 40F68R and 40F68RE are functionally equivalent for circuit applications requiring 68 Ohm, 10W axial wirewound resistors. Selection between these parts should be based on the following criteria:

40F68R is suitable for applications where RoHS non-compliant components are acceptable or required by design specifications.

40F68RE is the appropriate choice for applications subject to ROHS3 compliance requirements or where regulatory adherence to RoHS3 standards is mandatory. This part also offers higher current inventory availability at 1034 units.

Both parts maintain identical electrical performance, mechanical fit, and thermal characteristics. The choice between them is determined by compliance requirements and supply chain considerations rather than technical performance differences.

Frequently Asked Questions (FAQ)

Q: Can the 40F68RE be used as a direct replacement for the 40F68R?

A: Yes. The 40F68RE is a parametric equivalent with identical resistance value, tolerance, power rating, composition, package type, temperature coefficient, and physical dimensions. Direct substitution is possible without circuit redesign.

Q: What is the difference between the 40F68R and 40F68RE?

A: The primary differences are packaging format (standard vs. Bulk) and RoHS compliance status. The 40F68R is RoHS non-compliant, while the 40F68RE is ROHS3 compliant. All electrical and mechanical specifications are identical.

Q: Does the RoHS compliance difference affect circuit performance?

A: No. RoHS compliance status relates to material composition and environmental regulations, not electrical performance. Both parts deliver identical resistance, tolerance, power handling, and temperature stability.

Q: Are the physical dimensions identical between these parts?

A: Yes. Both the 40F68R and 40F68RE measure 0.406" diameter by 1.902" length (10.30mm x 48.30mm). They are mechanically interchangeable in PCB layouts and through-hole applications.

Q: Which part should I select for new designs?

A: For new designs subject to RoHS3 regulations or environmental compliance requirements, the 40F68RE is the appropriate selection. For applications without RoHS compliance mandates, either part is suitable based on availability and supply chain preferences.