Is there a pin-compatible replacement for SQT3.15M?

No replacement has been confirmed as 100% pin-compatible without manual verification. Parts from the same SQT series (like SQT5.00M) are likely pin-compatible but have different current ratings. The SMT1315A is electrically similar but its package dimensions must be checked.

What risks should I check before replacing SQT3.15M?

Before replacing SQT3.15M, you must check two key things. First, ensure the replacement's current rating is exactly 3.15A; a higher value will not protect your circuit correctly. Second, verify the physical dimensions (package size and lead spacing) to ensure it fits on your board.

SQT3.15M Alternatives, Datasheet & Cross Reference | TLC Electronic

Finding a substitute for the TLC Electronic SQT3.15M, a 3.15A 300V slow-blow fuse, requires careful attention to both electrical ratings and physical package. While several functional alternatives exist, no direct drop-in replacement has been confirmed.

AI replacement insight

Package riskhigh

Candidates have different form factors (e.g., micro fuse vs. square) requiring PCB layout and spacing checks.

Electrical riskmedium

Most alternatives have higher current ratings, which is a critical functional change. One candidate matches current.

Sourcing risklow

Multiple manufacturers offer fuses with similar through-hole packages and electrical ratings.

Can it be replaced directly?

No confirmed direct drop-in replacement exists. While parts from the same TLC SQT series share the package, they have different current ratings. The closest functional match, SMT1315A, requires mechanical verification.

Best replacement path

The LANSON SMT1315A is the best electrical match, offering the same 3.15A current and a higher 400V rating. However, its 'micro fuse' package differs from the target's 'square' package, so physical compatibility must be verified.

Main risk

The primary risks are package incompatibility and incorrect current ratings. Using a fuse with a higher current rating will compromise circuit protection.

Recommended alternatives

A functional alternative with matching current and higher voltage, but requires package and pinout verification.

View details

Alternative comparison matrix

Feature / factor	SQT3.15M	SMT1315A	SQT5.00M	Compatibility / risk
Current	3.15A	3.15A	5.0A	3.15A / 5.0A — Current rating matches the target.; SQT5.00M: Higher current rating will not protect the circuit at the original 3.15A level.
Voltage	300V	400V	300V	400V / 300V — Higher voltage rating provides more margin.; SQT5.00M: Voltage rating matches.
Package	Through Hole (Square Plastic)	Through-Hole (Micro Fuse)	Through Hole	Through-Hole (Micro Fuse) / Through Hole — Package form factor may differ. Target is 'Square Plastic'.; SQT5.00M: Same package family, likely form-fit compatible.
Manufacturer	TLC Electronic	LANSON	TLC Electronic	LANSON / TLC Electronic — Cross-vendor alternative.; SQT5.00M: Same manufacturer and product family.

Application & sourcing insights

Questions & answers

The best alternative is likely the LANSON SMT1315A, which matches the 3.15A current and has a higher 400V voltage rating. However, you must verify that its physical package fits your PCB layout, as it may differ from the original.