TVS diode naming convention and identification of positive and negative poles

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Today, while welding the TVS diode in the power supply board, I failed to pay attention to the positive and negative poles, which resulted in a voltage output of almost zero. It took me a long time to figure out that the problem was caused by the diode’s poles being welded in the wrong order. Therefore, I also looked up the markings for the positive and negative poles of TVS diodes, as well as their naming conventions. SMBJ naming convention: The model of a TVS diode consists of three parts: the series name + voltage value + single/dual-direction symbol. SMAJ, SMBJ, SMCJ, and SMDJ denote surface-mount packages; the peak pulse powers they correspond to are 400W, 600W, 1500W, and 3000W respectively. 2. The number following the series name represents the nominal breakdown voltage or the reverse off-state voltage value. 3. A denotes one-way, while CA denotes two-way. The section of the tube marked with a black line is its negative pole, which is the same as in tantalum capacitors; this is the opposite of how polarized components are labeled, so it’s important to keep this in mind.