B8J20K Equivalent & Substitute Parts

Part Overview

The B8J20K is a 20 kOhms ±5% 8W through-hole axial wirewound resistor manufactured by Ohmite, part of the Brown Devil® 200 series. This component is designed for applications requiring high power dissipation in a compact axial package with flame retardant coating and safety features. The part maintains active product status with 870 units in current inventory. Substitute parts are identified when equivalent electrical specifications and mechanical compatibility allow direct replacement in circuit designs.

Substiute Parts

B8J20K

OhmiteIn Stock: 904B8J20K Datasheet

Current PartRFQ

20J20KE

OhmiteIn Stock: 339420J20KE Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The 20J20KE qualifies as a substitute for the B8J20K based on the following critical parameters:

• Resistance Value: Both parts are 20 kOhms ±5%, ensuring electrical equivalence in circuit operation
• Composition: Both are wirewound resistors with identical flame retardant coating and safety features
• Package Type: Both use axial through-hole packaging, permitting direct mechanical installation
• Termination Count: Both feature 2 terminations, maintaining identical circuit connectivity

The 20J20KE differs in power rating (10W versus 8W) and temperature coefficient (±30ppm/°C versus ±260ppm/°C), representing an upgrade path for applications requiring improved thermal stability or higher power dissipation margins.

Parameter Comparison

Engineering Selection Recommendations

Both the B8J20K and 20J20KE are active products from Ohmite with identical resistance and tolerance specifications. The 20J20KE offers ROHS3 compliance, whereas the B8J20K is RoHS non-compliant. Selection between these parts depends on regulatory requirements and physical space constraints. The 20J20KE's larger physical dimensions (0.394" Dia x 1.858" L) must be verified against available board layout space. The 20J20KE's superior temperature coefficient (±30ppm/°C) provides enhanced stability in temperature-sensitive applications compared to the B8J20K (±260ppm/°C). The 10W power rating of the 20J20KE accommodates higher dissipation margins than the 8W rating of the B8J20K.

Frequently Asked Questions (FAQ)

Q: Can the 20J20KE directly replace the B8J20K in all applications?

A: Direct replacement is possible for applications where the larger physical dimensions of the 20J20KE (0.394" Dia x 1.858" L versus 0.313" Dia x 1.000" L) do not conflict with board layout constraints. Electrical performance is equivalent due to matching resistance, tolerance, and composition specifications.

Q: What is the significance of the temperature coefficient difference?

A: The 20J20KE exhibits a temperature coefficient of ±30ppm/°C compared to the B8J20K at ±260ppm/°C. This indicates the 20J20KE maintains more stable resistance values across temperature variations, beneficial for precision circuits or wide operating temperature ranges.

Q: Does RoHS compliance affect electrical performance?

A: RoHS compliance status does not alter electrical characteristics. The 20J20KE's ROHS3 compliance addresses regulatory and environmental requirements for specific markets and applications, whereas the B8J20K's non-compliant status may restrict use in regulated industries.

Q: Are both parts suitable for high-power applications?

A: The B8J20K is rated for 8W dissipation, while the 20J20KE is rated for 10W. Selection depends on the actual power dissipation requirements of the circuit. The 20J20KE provides additional thermal margin for applications approaching the 8W limit.

Q: What packaging considerations apply to substitution?

A: Both parts use axial through-hole packaging with 2 terminations, ensuring compatible circuit board mounting. However, the 20J20KE's larger diameter and length require verification of available board space before substitution.