USB ESD PROTECTION CIRCUIT

摘要

A circuit for USB protecting against electrostatic discharge includes a diode array, a zener diode, and a voltage protection circuit. The positive pole of the zener diode is grounded and coupled to a first terminal of the diode array. The negative pole of the zener diode is coupled to a second terminal and a first port of the voltage protection circuit. Two nodes of the diode array are coupled to a pair of data ports of a USB connector. A second port of the voltage protection circuit is coupled to a power port. When the power port has a low level of voltage and the first or second data port has a high level of voltage, the circuit switches off the connection between the diode array and the power port, preventing the low level of voltage from being changed to high level of voltage.

主权项

1. A universal serial bus (USB) electro-static discharge (ESD) protection circuit comprising:
a first diode array; a zener diode coupled to two terminals of the first diode array; and a voltage protection circuit; wherein the positive pole of the zener diode is grounded and coupled to a first terminal of the first diode array; the negative pole of the zener diode is coupled to a second terminal of the first diode array and a first port of the voltage protection circuit; two nodes of the first diode array are configured to couple to a pair of data ports of a USB connector; static in each data port is guide to the ground by the zener diode via the first diode array; and a second port of the voltage protection circuit is configured to couple to a power port of the USB connector; and wherein when the power port has a low level of voltage and the first data port or the second data port has a high level of voltage, the voltage protection circuit switches off the connection between the first diode array and the power port, preventing the low level of voltage of the power port from being changed to the high level of voltage.