Equivalent & Substitute Parts for Ohmite 805F20K

Part Overview

The Ohmite 805F20K is a 20 kOhms ±1% 5W wirewound chassis mount resistor designed for applications requiring precision resistance with moderate power dissipation. This component features aluminum housing with flanged mounting and solder lug termination, suitable for fixed installation in electronic equipment.

The 805F20K carries an Obsolete product status, indicating it is no longer in active production. Identifying qualified substitute components ensures design continuity and maintains supply chain reliability for legacy systems or new designs requiring equivalent electrical and mechanical characteristics.

Substiute Parts

805F20K

OhmiteIn Stock: 818805F20K Datasheet

Current PartRFQ

UAL5-20KF8

RiedonIn Stock: 967UAL5-20KF8 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 805F20K is determined by the following critical parameters:

• Resistance Value: Must be 20 kOhms
• Tolerance: Must be ±1% or tighter
• Composition: Must be wirewound
• Temperature Coefficient: Must be ±20ppm/°C or better
• Operating Temperature Range: Must encompass -55°C to 275°C
• Housing Material: Must be aluminum
• Mounting Feature: Must include flanges
• Lead Style: Must be solder lugs
• Package Configuration: Must be axial with box packaging

The Riedon UAL5-20KF8 meets all substitution criteria. While it provides a higher power rating (7.5W versus 5W), this represents an enhancement that maintains backward compatibility with the original design specification. The identical resistance value, tolerance, temperature coefficient, operating range, housing material, mounting configuration, and lead style ensure mechanical and electrical interchangeability.

Parameter Comparison

Engineering Selection Recommendations

The Riedon UAL5-20KF8 is the qualified substitute for the Ohmite 805F20K based on the following factors:

Electrical Equivalence: Both components share identical resistance value (20 kOhms), tolerance (±1%), temperature coefficient (±20ppm/°C), and operating temperature range (-55°C to 275°C). These parameters ensure functional interchangeability in circuit applications.

Mechanical Compatibility: Both resistors feature aluminum housing with flanged mounting and solder lug termination. Physical dimensions are nearly identical (0.598" L × 0.646" W for UAL5-20KF8 versus 0.600" L × 0.646" W for 805F20K), with height differences within acceptable tolerances for standard PCB layouts.

Power Rating Enhancement: The UAL5-20KF8 provides 7.5W power dissipation compared to the 805F20K's 5W rating. This higher rating does not compromise compatibility and may provide improved thermal margin in applications operating near the original component's power limits.

Compliance Status: The UAL5-20KF8 is ROHS3 compliant and carries Active product status, ensuring long-term availability and regulatory alignment for new designs or legacy system updates.

Frequently Asked Questions (FAQ)

Q: Can the Riedon UAL5-20KF8 directly replace the Ohmite 805F20K in existing designs?

A: Yes. Both components are electrically and mechanically equivalent. The UAL5-20KF8 provides identical resistance, tolerance, temperature coefficient, and operating range. Physical dimensions are compatible with standard mounting configurations. The higher power rating (7.5W) does not affect compatibility.

Q: What is the significance of the higher power rating on the substitute part?

A: The UAL5-20KF8's 7.5W rating versus the 805F20K's 5W rating indicates improved thermal performance. This enhancement maintains backward compatibility while potentially extending component life in applications with sustained power dissipation near the original specification limit.

Q: Are there compliance differences between these components?

A: Yes. The 805F20K is RoHS non-compliant, while the UAL5-20KF8 is ROHS3 compliant. For new designs or systems requiring regulatory compliance, the UAL5-20KF8 is the appropriate selection.

Q: How do the physical dimensions compare?

A: Dimensions are nearly identical. The 805F20K measures 0.600" L × 0.646" W × 0.330" H (seated), while the UAL5-20KF8 measures 0.598" L × 0.646" W × 0.335" H (seated). These differences are within standard PCB layout tolerances and do not affect mounting compatibility.

Q: What is the product status difference, and why does it matter?

A: The 805F20K is Obsolete and no longer manufactured. The UAL5-20KF8 is Active, ensuring reliable long-term availability. For new designs or system updates, the Active status component is recommended to avoid future supply chain constraints.

Q: Are the lead styles identical?

A: Yes. Both components feature solder lug termination, ensuring compatibility with existing PCB designs and assembly processes.