78FR10M Equivalent & Substitute Parts

Part Overview

The 78FR10M is a 100 nH unshielded drum core wirewound inductor rated for 500 mA with a maximum DC resistance of 60 mOhm, designed for through-hole axial mounting. This component is classified as obsolete, making identification of suitable alternatives essential for ongoing design support and production continuity. The 78F series inductors are ferrite-core devices suitable for high-frequency applications up to 400 MHz self-resonant frequency.

Substiute Parts

78FR10M

Bourns Inc.In Stock: 78678FR10M Datasheet

Current PartRFQ

78FR10M-RC

Bourns Inc.In Stock: 616478FR10M-RC Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 78FR10M is determined by the following critical parameters:

• Inductance Value: Must be 100 nH with ±20% tolerance
• Core Type and Shielding: Must be ferrite-core, unshielded drum core construction
• Mounting Configuration: Must be through-hole axial package with identical physical dimensions (0.110" Dia x 0.280" L)
• Operating Temperature Range: Must support -55°C to 105°C minimum
• DC Resistance: Must not exceed 60 mOhm maximum
• Self-Resonant Frequency: Must be 400 MHz or higher

The substitute part 78FR10M-RC meets all these criteria while offering an increased current rating of 1.2 A compared to the original 500 mA specification. This higher current capacity makes it suitable for applications requiring the same inductance and electrical characteristics but with greater current handling capability.

Parameter Comparison

Engineering Selection Recommendations

The 78FR10M-RC is the direct substitute for the obsolete 78FR10M. Both components share identical electrical specifications for inductance, DC resistance, core material, and frequency characteristics. The primary differences are:

Product Status: The 78FR10M is obsolete, while the 78FR10M-RC is active and currently in production with 6062 units in stock versus 748 units of the original part.

Regulatory Compliance: The 78FR10M-RC is RoHS3 compliant, whereas the original 78FR10M is RoHS non-compliant. This compliance status is significant for applications subject to RoHS regulations.

Current Rating: The 78FR10M-RC provides 1.2 A current rating compared to 500 mA for the original part. This increased capacity is a direct upgrade that maintains backward compatibility for circuits designed around the 500 mA specification.

Packaging: The 78FR10M-RC is supplied in bulk packaging, whereas the original part packaging is unspecified.

For new designs or production transitions, the 78FR10M-RC is the appropriate selection due to its active status, regulatory compliance, and superior current handling capability.

Frequently Asked Questions (FAQ)

Q: Can the 78FR10M-RC be used as a direct replacement for the 78FR10M in existing designs?

A: Yes. The 78FR10M-RC maintains identical inductance (100 nH), DC resistance (60 mOhm max), core material (ferrite), shielding (unshielded), mounting type (through-hole axial), physical dimensions (0.110" Dia x 0.280" L), and operating temperature range (-55°C to 105°C). The increased current rating of 1.2 A versus 500 mA represents an upgrade that does not compromise compatibility.

Q: What are the key electrical parameters that define substitution eligibility?

A: Substitution is determined by inductance value (100 nH ±20%), DC resistance (60 mOhm maximum), core type (ferrite unshielded), self-resonant frequency (400 MHz), and physical package dimensions (0.110" Dia x 0.280" L axial). All these parameters must match or exceed the original specification.

Q: Why is the 78FR10M-RC preferred over the obsolete 78FR10M?

A: The 78FR10M-RC is an active product with current manufacturing support and higher inventory availability. It also meets RoHS3 compliance requirements, making it suitable for regulated applications. The increased current rating provides additional design margin without changing the core electrical characteristics.

Q: Are there any mechanical compatibility concerns when substituting the 78FR10M-RC?

A: No. Both components share identical physical dimensions (0.110" Dia x 0.280" L) and axial through-hole mounting configuration, ensuring direct mechanical compatibility on PCBs designed for the original 78FR10M.

Q: What is the significance of the Q factor difference between these parts?

A: The 78FR10M specifies Q @ 25 MHz of 40, while the 78FR10M-RC specifies Q @ 25 MHz of 20. Both values are measured at the same frequency and represent the quality factor at that test condition. The lower Q value in the substitute part is a characteristic of its higher current rating design but does not affect substitution eligibility for applications requiring 100 nH inductance.