Automotive-grade 400 W TVS in the SMA footprint
The SMAJ43AQ-13-F: It carries AEC-Q101 automotive qualification, meaning the device has passed the reliability stress tests and temperature cycling required for automotive-grade components — suitable for 12 V and 24 V vehicle electrical systems where load-dump and inductive-switch transients are a concern. The operating junction temperature range spans -55°C to 150°C, covering the under-hood and cabin ambient extremes without derating the 400 W pulse capability at the high end.
Breakdown voltage (V_BR) is specified at a minimum of 47.8 V, which is the point where the Zener junction starts to avalanche and conduct. The 69.4 V clamping voltage (V_C) is the maximum voltage the protected circuit sees when the TVS is shunting the full 5.7 A peak pulse current. With a single unidirectional channel, this part protects one rail per device — the cathode is the protected line, the anode goes to ground. For bidirectional protection on AC-coupled or bipolar rails, two devices or a dedicated bidirectional TVS would be needed.
Package and board-fit: DO-214AC SMA
The supplier device package is designated SMA, confirming the JEDEC-standard outline with a 2.6 mm body width and gull-wing leads. Tape-and-reel packaging supports automated pick-and-place assembly at volume.