78F8R2J Equivalent & Substitute Parts

Part Overview

The 78F8R2J is an 8.2 µH unshielded drum core wirewound inductor manufactured by Bourns Inc., rated for 155 mA maximum current with 550mOhm DC resistance. This through-hole axial component operates across -55°C to 105°C and is designed for applications requiring fixed inductance in compact form factors.

The 78F8R2J is classified as obsolete. Locating equivalent or substitute components becomes necessary when original stock is depleted or when design requirements allow for compatible alternatives that offer improved availability or enhanced specifications.

Substiute Parts

78F8R2J

Bourns Inc.In Stock: 103478F8R2J Datasheet

Current PartRFQ

78F8R2J-RC

Bourns Inc.In Stock: 7132078F8R2J-RC Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 78F8R2J is based on the following critical parameters that must remain constant or compatible:

• Inductance Value: 8.2 µH (±5% tolerance maintained)
• Core Type & Material: Ferrite drum core, unshielded
• Mounting Configuration: Through-hole axial package
• Physical Dimensions: 0.110" Dia x 0.280" L
• Operating Temperature Range: -55°C to 105°C
• DC Resistance: 550mOhm Max

The substitute part 78F8R2J-RC shares identical inductance, core material, shielding, dimensions, and temperature range. The primary difference is an increased current rating (425 mA versus 155 mA), which represents an upward-compatible specification. This higher current capacity does not compromise circuit performance in applications designed for the original 155 mA rating.

Parameter Comparison

Engineering Selection Recommendations

The 78F8R2J-RC is a direct substitute for the 78F8R2J based on electrical and mechanical compatibility. Both components share identical inductance, DC resistance, core material, physical dimensions, and operating temperature specifications.

The 78F8R2J-RC offers two significant advantages:

1. Product Status: The 78F8R2J-RC maintains active production status, ensuring long-term availability and supply chain reliability compared to the obsolete 78F8R2J.

2. Regulatory Compliance: The 78F8R2J-RC is ROHS3 compliant, whereas the 78F8R2J is non-compliant. For applications subject to RoHS regulations or customer requirements, the 78F8R2J-RC satisfies current environmental standards.

The increased current rating of 78F8R2J-RC (425 mA versus 155 mA) does not create incompatibility. Circuits designed for 155 mA operation will function identically with the higher-rated substitute, as the component will operate well within its specified limits.

Frequently Asked Questions (FAQ)

Q: Can 78F8R2J-RC be used as a direct replacement for 78F8R2J in existing designs?

A: Yes. Both components have identical inductance (8.2 µH), DC resistance (550mOhm Max), core material (ferrite), shielding (unshielded), physical dimensions (0.110" Dia x 0.280" L), and operating temperature range (-55°C to 105°C). The higher current rating of 78F8R2J-RC does not affect compatibility in circuits designed for 155 mA operation.

Q: What is the primary reason to substitute 78F8R2J with 78F8R2J-RC?

A: The 78F8R2J is obsolete with limited stock availability. The 78F8R2J-RC is in active production, providing reliable long-term supply. Additionally, 78F8R2J-RC meets ROHS3 compliance requirements, whereas 78F8R2J does not.

Q: Are the physical dimensions identical between these two parts?

A: Yes. Both components measure 0.110" diameter by 0.280" length (2.79mm x 7.11mm), ensuring identical PCB footprint and mounting compatibility.

Q: Does the higher current rating of 78F8R2J-RC affect circuit performance?

A: No. A component with higher current rating specifications operates safely at lower current levels. In applications where 78F8R2J is rated for 155 mA, the 78F8R2J-RC will perform identically without performance degradation.

Q: Are there any electrical parameter differences that would prevent substitution?

A: No. The inductance value, tolerance, DC resistance, Q factor, operating temperature range, and self-resonant frequency are identical between both parts. Substitution is electrically transparent.