Is there a pin-compatible replacement for BSMD1812-400-12V?

Several parts like JK-MSMD500L-12V share the 1812 package, making them pin-compatible. However, their electrical parameters, especially hold current, differ and must be verified.

What risks should I check before replacing BSMD1812-400-12V?

The main risk is using a replacement with a higher hold current, which may fail to protect your circuit from overcurrent conditions. Also check max voltage, max fault current, and trip time.

BSMD1812-400-12V Alternatives, Datasheet & Cross Reference | BHFUSE

BSMD1812-400-12V is a 4A, 12V PTC resettable fuse in an 1812 package. Finding a direct replacement requires matching hold/trip currents and voltage ratings to ensure proper circuit protection.

AI replacement insight

Electrical riskhigh

All candidates have higher hold currents, which compromises overcurrent protection.

Package risklow

All viable candidates match the 1812 package, ensuring physical compatibility.

Can it be replaced directly?

No direct, drop-in replacement was found. All candidates have different current ratings that require engineering validation.

Best replacement path

Use a functional alternative like JK-MSMD500L-12V after verifying the higher 5A hold current is acceptable for the application.

Main risk

Using a part with a higher hold current can lead to circuit damage by not tripping at the intended threshold.

Recommended alternatives

A functional alternative in the same 1812 package, but with a higher 5A hold current that requires engineering review.

View details

Alternative comparison matrix

Feature / factor	BSMD1812-400-12V	JK-MSMD500L-12V	BSMD1812L-600-12V	Compatibility / risk
Package	1812	1812	1812	1812 — Form and fit are compatible.; BSMD1812L-600-12V: Form and fit are compatible.
Current	40A	50A	6.0A	50A / 6.0A — Higher max fault current rating is an improvement.; BSMD1812L-600-12V: Hold current is 50% higher, a significant deviation.
Voltage	12.0V	12.0V	12.0V	12.0V — Maximum voltage rating matches.; BSMD1812L-600-12V: Maximum voltage rating matches.
Power	2.0W	1.8W	-	1.8W — Lower power dissipation may affect thermal characteristics.

Application & sourcing insights

Questions & answers

JK-MSMD500L-12V is a potential functional alternative, but has a higher 5A hold current. Engineering review is essential to ensure circuit protection is not compromised.