The 1.5SMC22CA-Q: The large tab on the bottom side carries the cathode for the bidirectional pair — the PCB copper pad area under this tab sets the junction-to-ambient thermal resistance, so the board layout directly determines how much of the 1500 W peak pulse the device can absorb without exceeding the 150 °C junction limit. The tape-and-reel packaging supports high-volume pick-and-place assembly.
Clamping performance and selection fit
The 49.7 A peak pulse current figure is the current at which the clamping voltage is specified — a lower surge current results in a lower clamp voltage, so the actual protection level depends on the source impedance of the transient.
Automotive qualification and series identity
The 1.5SMC22CA-Q belongs to the Bourns 1.5SMC-Q series, which carries AEC-Q101 qualification. The Q suffix in the order code denotes the automotive-grade variant of the standard 1.5SMC22CA.