2. 1.5SMC13A-E3/9AT Substitution Conclusion The 1.5SMC13A-E3/9AT is a viable substitute for the original part in terms of primary protection performance, though minor specification differences should be noted. This device, manufactured by Vishay, shares identical core protection parameters (reverse standoff voltage, breakdown voltage, clamping voltage, peak power rating) and package with the original, ensuring baseline protection functionality and mechanical compatibility. The difference lies in its specified peak pulse current (Ipp) of 82.4A, which is slightly lower than the original's 83.5A. Under theoretically identical high-current transient conditions, the Vishay component offers a marginally smaller design margin. However, for a 1500W power rating, this difference (approximately 1.3%) is minimal and can generally be considered equivalent in practical circuit protection applications. The substitution is feasible, but if the application has extremely stringent requirements for surge current margin, this variance should be taken into account.