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Protection plate short circuit protection control principle:

2021-11-02

In the process of external discharge of the protection plate, the two electronic switches in 8205A are not completely equivalent to two mechanical switches, but equivalent to two resistors with very small resistance, which is called the internal resistance of the conduction of 8205A. The internal resistance of the conduction of each switch is about 30m\U 03A9, which is about 60m\U 03A9. The voltage applied to the G pole is actually a direct control of the size of the on-resistance of each switch tube. When the G pole voltage is greater than 1V, the on-resistance of the switch tube is very small (tens of milliohms), which is equivalent to the switch closed. When the G-pole voltage is less than 0.7V, the on-resistance of the switch tube is very large (several M ω), which is equivalent to the switch off. The voltage UA is the voltage generated by the internal resistance of 8205A and the discharge current. When the load current increases, UA will inevitably increase. Because UA0.006L×IUA is also called the pipe pressure drop of 8205A, UA can be simply connected to indicate the size of the discharge current. When it rises to 0.2V, it thinks that the load current has reached the limit value, so it stops the output voltage of the first foot and changes the voltage of the first foot to 0V. The discharge control tube within 8205A is closed, and the discharge circuit of the cell is cut off. The discharge control tube will be shut off. In other words, the maximum allowable output current of DW01 is 3.3a, which achieves over-current protection.

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