When this lead line touches the positive extreme of a certain stroke, that stroke should be displayed. With this simple method, you can check whether the digital tube has broken pens (some strokes cannot be displayed), continuous strokes (some strokes are connected together), and relatively compare the strength of different strokes. If you can check the total For anode digital tube, only need to reverse the battery's positive and negative lead wires, the method is the same as above.

　　The working current ILED of each stroke of the LED digital tube is about 5-10mA. If the current is too high, the digital tube will be damaged, so a current-limiting resistor must be added. The resistance value can be calculated as follows:

　　R value=(U-ULED)／ILED

　　 where U is the voltage applied across the LED, and ULED is the voltage drop per stroke of the LED digital tube (about 2 volts). The hFE socket of the digital multimeter can be used to conveniently check the light-emitting condition of the LED digital tube. When the NPN gear is selected, the C hole is positively charged and the moon hole is negatively charged.

For example, when checking the LTS547R type common cathode LED digital tube, insert a single thin wire from hole E, and the lead end of the wire is connected to 9 poles (pin ③ and pin ⑧ are connected internally, you can choose one as ?); C hole leads to a wire to contact each pen segment electrode in turn, and the corresponding pen segment can be displayed respectively. At the same time, you can go to our product center and leave a message for consultation.