Is there a pin-compatible replacement for JK250-180U?

JK250-180T shares the same radial leaded package and pin count. While it is form-fit compatible, its different electrical characteristics, especially a slower trip time, mean it is not a direct drop-in replacement without review.

What risks should I check before replacing JK250-180U?

The main risks are electrical. Verify the slower trip time of any alternative is acceptable for your circuit's safety margins. Also check for differences in resistance, which can affect in-rush current behavior and voltage drop.

JK250-180U Alternatives, Datasheet & Cross Reference | NK Technologies

Finding a substitute for the JK250-180U PTC resettable fuse requires careful matching of hold current, voltage, and trip time. While some parts share the same package and key ratings, differences in trip characteristics pose a risk.

AI replacement insight

Electrical riskhigh

Slower trip time and different resistance require re-validation.

Package risklow

Package is a compatible radial leaded type.

Sourcing riskmedium

Alternative is from a different manufacturer, requiring vendor qualification.

Can it be replaced directly?

No direct drop-in replacement has been identified. The closest candidate, JK250-180T, has a slower trip time which is a critical safety parameter.

Best replacement path

The best path is to evaluate JK250-180T, but only if the application can tolerate a trip time of 3 seconds instead of 1.5 seconds.

Main risk

The primary risk is a slower trip time, which could lead to damage in the protected circuit during an overcurrent event.

Recommended alternatives

A functional alternative with the same voltage and hold current, but slower trip time requires engineering review.

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Alternative comparison matrix

Feature / factor	JK250-180U	JK250-180T	Compatibility / risk
Package	Radial Leaded	Radial Leaded	Radial Leaded — Same package and pin count.
Voltage	250V	250V	250V — Voltage rating matches.
Current	180mA	180mA	180mA — Hold current matches.
Trip Time	1.5s	3s	3s — Slower trip time increases risk to protected circuit.
Resistance	2.0-4.0Ω	1.0-2.2Ω	1.0-2.2Ω — Different initial resistance range may affect circuit behavior.

Application & sourcing insights

Questions & answers

JK250-180T is a potential functional alternative with the same 250V rating and 180mA hold current. However, its trip time is slower (3s vs 1.5s), which requires careful engineering review to ensure circuit safety.