NF08AA0509MHB Equivalent & Substitute Parts

Part Overview

The NF08AA0509MHB is an inrush current limiter manufactured by KYOCERA AVX, designed to limit inrush current in power supply circuits. This component features a 5 ohm resistance at 25°C with ±20% tolerance and supports a steady-state maximum current of 2.9 A. The part is housed in an 8mm diameter package with 5.08mm lead spacing.

The NF08AA0509MHB is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity and ensure component availability for new production runs, repairs, and system upgrades.

Substiute Parts

NF08AA0509MHB

KYOCERA AVXIn Stock: 1176NF08AA0509MHB Datasheet

Current PartRFQ

B57153S0479M000

EPCOS - TDK ElectronicsIn Stock: 31841B57153S0479M000 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the NF08AA0509MHB is determined by the following critical parameters:

• Resistance Value: The substitute must operate within the tolerance band of the original part. The NF08AA0509MHB specifies 5 Ohms ±20%, establishing an acceptable range of 4.0 to 6.0 Ohms.
• Steady-State Current Rating: The substitute must support the required current level without exceeding thermal limits.
• Package Dimensions: Physical compatibility requires similar diameter and lead spacing to ensure proper mounting and circuit board integration.
• Tolerance: Electrical tolerance must match or exceed the original specification to maintain circuit performance.

The B57153S0479M000 qualifies as a substitute based on these parameters: it provides 4.7 Ohms (within the 4.0–6.0 Ohm range), supports 3 A steady-state current (exceeding the 2.9 A requirement), and maintains ±20% tolerance with compatible package dimensions.

Parameter Comparison

Engineering Selection Recommendations

The B57153S0479M000 is the qualified substitute for the NF08AA0509MHB based on the following factors:

• Product Status: The original part is obsolete, while the substitute is active and maintains current manufacturing support.
• Electrical Compatibility: The 4.7 Ohm resistance falls within the acceptable tolerance band of the original 5 Ohm specification. The 3 A steady-state current rating exceeds the original 2.9 A requirement, providing operational margin.
• Compliance: The substitute achieves ROHS3 compliance and carries UL approval, improving regulatory alignment compared to the non-compliant original part.
• Package Compatibility: Lead spacing differs by 0.03" (0.08mm), and diameter differs by 0.02" (0.50mm). These minor dimensional variations are within typical PCB layout tolerances for through-hole inrush current limiters.

Frequently Asked Questions (FAQ)

Q: Can the B57153S0479M000 directly replace the NF08AA0509MHB without circuit modifications?

A: Yes. The electrical parameters (resistance, tolerance, and current rating) are compatible. Minor package dimension differences (0.02" diameter, 0.03" lead spacing) are within standard PCB layout tolerances for this component category.

Q: Why does the substitute have a lower resistance value (4.7 Ohms vs. 5 Ohms)?

A: Both parts operate under ±20% tolerance. The 4.7 Ohm value falls within the acceptable range of the original specification (4.0–6.0 Ohms) and provides equivalent circuit performance.

Q: What is the impact of the higher current rating (3 A vs. 2.9 A)?

A: The higher rating provides additional thermal margin and operational headroom. This does not negatively affect circuit performance and may improve component longevity.

Q: Does the RoHS3 compliance of the substitute affect compatibility?

A: No. RoHS3 compliance is a manufacturing and environmental standard that does not alter electrical or mechanical compatibility. It represents an improvement over the non-compliant original part.

Q: Are there any lead spacing concerns?

A: The lead spacing difference is 0.03" (0.08mm), which is negligible for standard PCB through-hole designs. Existing footprints will accommodate this substitute without modification.