78FR33K Equivalent & Substitute Parts

Part Overview

The 78FR33K is a 330 nH unshielded drum core wirewound inductor manufactured by Bourns Inc., rated for 815 mA with a maximum DC resistance of 80 mOhm. This component is designed for through-hole axial mounting applications requiring low inductance values with high current capacity. The 78FR33K is classified as obsolete, making identification of functionally equivalent substitute parts essential for ongoing design support and production continuity.

Substiute Parts

78FR33K

Bourns Inc.In Stock: 93278FR33K Datasheet

Current PartRFQ

8230-08-RC

Bourns Inc.In Stock: 8808230-08-RC Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 78FR33K is determined by the following critical parameters:

• Inductance Value: 330 nH (primary electrical specification)
• Inductance Tolerance: ±10% (acceptable variation range)
• Current Rating: Minimum 780 mA (substitute must support circuit current demands)
• DC Resistance: Maximum 200 mOhm (acceptable upper limit for power dissipation)
• Operating Temperature Range: -55°C to 105°C (environmental compatibility)
• Mounting Type: Through Hole Axial (mechanical compatibility)
• Package / Case: Axial (form factor compatibility)

The 8230-08-RC qualifies as a substitute based on matching inductance, tolerance, temperature range, and mounting specifications. While the substitute exhibits higher DC resistance (200 mOhm vs. 80 mOhm) and slightly lower current rating (780 mA vs. 815 mA), these parameters remain within acceptable operational limits for equivalent circuit functionality.

Parameter Comparison

Engineering Selection Recommendations

The 8230-08-RC serves as the primary substitute for the obsolete 78FR33K. Selection should be based on the following factors:

Product Status: The 78FR33K is obsolete, while the 8230-08-RC is active and maintains current manufacturing support from Bourns Inc.

Regulatory Compliance: The 8230-08-RC is ROHS3 compliant, whereas the 78FR33K is RoHS non-compliant. For applications subject to RoHS regulations, the 8230-08-RC is the required choice.

Electrical Performance: Both parts share identical inductance (330 nH) and tolerance (±10%) specifications. The 8230-08-RC exhibits higher DC resistance (200 mOhm vs. 80 mOhm) and marginally lower current rating (780 mA vs. 815 mA). Circuit designs operating near the 815 mA threshold should account for the reduced current margin in the substitute.

Mechanical Compatibility: Both components are through-hole axial inductors with compatible form factors, supporting direct board-level substitution.

Frequently Asked Questions (FAQ)

Q: Can the 8230-08-RC directly replace the 78FR33K in existing designs?

A: Yes, the 8230-08-RC is mechanically and electrically compatible for direct substitution. Both components share identical inductance values, tolerance specifications, and operating temperature ranges. Designs must account for the higher DC resistance of the substitute when calculating power dissipation.

Q: What is the impact of the higher DC resistance in the 8230-08-RC?

A: The 8230-08-RC exhibits 200 mOhm maximum DC resistance compared to 80 mOhm in the 78FR33K. This increases resistive losses proportionally to the square of the current. For circuits operating at maximum current ratings, power dissipation will increase accordingly. Thermal management should be evaluated for high-current applications.

Q: Does the lower current rating of the 8230-08-RC affect compatibility?

A: The 8230-08-RC is rated for 780 mA versus 815 mA for the 78FR33K. Circuits designed to operate below 780 mA experience no functional impact. Designs requiring currents between 780 mA and 815 mA must be re-evaluated for the substitute component.

Q: Are there packaging differences between these components?

A: Both the 78FR33K and 8230-08-RC are axial through-hole inductors. Physical dimensions differ slightly (78FR33K: 0.110" Dia x 0.280" L; 8230-08-RC: 0.120" Dia x 0.300" L), but both are compatible with standard through-hole PCB layouts.

Q: What is the significance of RoHS compliance for the 8230-08-RC?

A: The 8230-08-RC is ROHS3 compliant, meeting current environmental and hazardous substance restrictions. The 78FR33K is RoHS non-compliant. For applications subject to RoHS regulations or customer requirements, the 8230-08-RC is the mandated choice.

Q: Are both components suitable for the same frequency range?

A: Yes. Both components are tested at 25 MHz inductance frequency and exhibit self-resonant frequencies suitable for RF and high-frequency applications (78FR33K: 350 MHz; 8230-08-RC: 410 MHz).