Diode pins can be divided into positive and negative poles, and accurately distinguishing pin polarity before detection is a key step in detecting diodes As shown in Figures 9-36, generally speaking, the polarity of the diode pins can be identified based on identification information
Key points:
1. The diode circuit graphic symbol is printed on the housing, with one side of the vertical line being the negative pole of the diode and the other end being the positive pole of the diode.
2. The diode marked with a colored ring on the casing, with one end of the ring being the negative electrode and the other end being the positive electrode of the diode There is a difference in the length of the LED pins, with the longer end being the positive pole 4 high-power diodes, with one threaded end as the negative electrode and the other end as the positive electrode The rectifier diode is usually marked with a white ring on the black shell, with one end being the negative electrode and the other end being the positive electrodeNote:
Most diodes will be marked with polarity on the casing, some represented by circuit graphical symbols, and some marked with color rings or pin length features.
When identifying the polarity of diode pins installed on a circuit board, the polarity of the pins can be identified based on the labeled information near the diode or around the solder joint on the back In addition, you can also find the corresponding circuit drawing based on the circuit where the diode is located, and identify pin polarity based on the circuit graphic symbols in the drawingFunction of testing report:
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