Is there a pin-compatible replacement for FNR5040S3R3NT?

No direct pin-for-pin replacement with identical key parameters has been verified. Parts like YNR5040-4R7M have the same package and pinout but differ in inductance and current ratings, requiring engineering review.

What risks should I check before replacing FNR5040S3R3NT?

Key risks include lower current ratings, which can cause overheating or failure, and different inductance values, which will alter power converter performance (e.g., ripple current, transient response). Always verify the package footprint and height.

FNR5040S3R3NT Alternatives, Datasheet & Cross Reference | Shenzhen CJiang Technology Co., Ltd.

FNR5040S3R3NT is a 3.3µH, 3.9A SMD power inductor in a 5x5mm package. While no direct drop-in replacements are identified, several alternatives with different parameters exist that may be suitable after design review.

AI replacement insight

Electrical riskhigh

Most candidates have lower current ratings and different inductance values.

Package riskmedium

Some candidates have different footprints (e.g., 6x6mm vs 5x5mm), requiring a PCB change.

Can it be replaced directly?

No direct, drop-in replacement for FNR5040S3R3NT has been identified. All candidates require engineering review due to differences in current rating, inductance, or package.

Best replacement path

Evaluate YNR5040-4R7M for form-fit compatibility, but verify its lower current rating (3.0A vs 3.9A) and higher inductance (4.7uH vs 3.3uH) are acceptable for the application.

Main risk

Lower current handling capability in most alternatives, leading to potential overheating or failure.

Recommended alternatives

Same package size but has lower current ratings and different inductance; requires engineering review.

View details

Alternative comparison matrix

Feature / factor	FNR5040S3R3NT	YNR5040-4R7M	YNR6045-6R8M	Compatibility / risk
Package	5040 (5.0mm x 5.0mm)	5040 (5.0mm x 5.0mm)	6.0mm x 6.0mm	5040 (5.0mm x 5.0mm) / 6.0mm x 6.0mm — Same package footprint.; YNR6045-6R8M: Larger package, not a drop-in replacement.
Inductance	3.3 uH	4.7 uH	6.8 uH	4.7 uH / 6.8 uH — Higher inductance, will affect circuit performance.; YNR6045-6R8M: Higher inductance, will affect circuit performance.
Current	3.9 A	3.0 A	3.0 A	3.0 A — Lower rated current, risk of overheating.; YNR6045-6R8M: Lower rated current, risk of overheating.
Saturation Current	4.45 A	3.5 A	-	3.5 A — Lower saturation current, may saturate under peak loads.
Tolerance	±30%	±20%	-	±20% — Tighter tolerance is generally acceptable.
Resistance	31 mΩ	-	31 mΩ	31 mΩ — DCR is a match.

Application & sourcing insights

Questions & answers

YNR5040-4R7M shares the same 5x5mm package but has a higher inductance (4.7uH) and lower current rating (3.0A). It requires careful circuit re-evaluation before use.