Device identity and key ratings
The 1.5SMC350AHM3_A/H is a Zener-type TVS diode from Vishay's 1.5SMC series, part of the TransZorb® family, qualified to AEC-Q101 for automotive applications.
The SMC footprint is standard for 1.5 kW TVS diodes — the copper pad area under the cathode tab sets the junction-to-ambient thermal resistance, so the PCB layout should follow the recommended land pattern in the product drawing to achieve the rated pulse derating.
AEC-Q101 qualification and application fit
AEC-Q101 qualification means the part has passed the automotive-grade stress tests: temperature cycling, high-temperature reverse bias, and ESD robustness per the JEDEC JESD22 series. Listed applications include automotive and telecom — the 300 V standoff voltage suits 48 V board nets, traction inverter DC-link protection, and on-board charger transient suppression where the nominal rail sits well below the standoff threshold.