How to correctly determine the positive and negative poles of chip tantalum capacitors?
One end of the chip tantalum capacitor is marked with a horizontal line, which is the positive electrode of the chip tantalum capacitor, and the other end is the negative electrode. The long end of the lead tantalum capacitor is the positive electrode, and the short end is the negative electrode.
SMD tantalum capacitors are polar capacitors. The positive and negative poles cannot be reversed. In case of reverse connection, the tantalum capacitor will not work or fail.
The positive and negative poles of SMD tantalum capacitors are distinguished and measured. The black block with the mark on the tantalum capacitor is the negative pole. There are two semicircles on the capacitor position on the PCB, and the pin corresponding to the colored semicircle is the negative pole. The length of the pins is also used to distinguish the positive and negative poles as positive and short pins as negative.
When we don’t know the positive and negative poles of SMD tantalum capacitors, we can use a multimeter to measure them. The medium between the two poles of the capacitor is not an absolute insulator, and its resistance is not infinite, but a finite value, generally above 1000 megohms. The resistance between the two poles of the capacitor is called insulation resistance or leakage resistance, and only electrolytic capacitors When the positive pole of the electrolytic capacitor is connected to the positive power supply (the black test lead when the electricity is blocked), and the negative terminal is connected to the negative power supply (the red test lead when the electricity is blocked), the leakage current of the electrolytic capacitor is small (the leakage resistance is large).