Monitoring circuit and system for ESD protection device

摘要

A monitoring circuit and a monitoring system for electrostatic discharge (ESD) protective device are disclosed herein. The monitoring circuit includes an oscillating unit, a signal processing unit and a comparator. The oscillating unit includes a first monitoring end and a second monitoring end. The first monitoring end is configured to be electrically connected to an ESD protective device. The second monitoring end is configured to be electrically connected to ground. When the first monitoring end is not electrically contacted to a user's body or the second monitoring end is not connected to ground, the oscillating unit is configured to output an oscillating signal. The signal processing unit is electrically connected to the oscillating unit, and is configured to output a first voltage according to the oscillating signal. The comparator is configured to compare the first voltage and a reference voltage, and correspondingly output an alarm signal.

主权项

1. A monitoring circuit, configured to be electrically connected to an electrostatic discharge (ESD) protection device and a ground line, the ESD protection device being configured to be in contact with a users body, the ground line is configured to be connected to the ground, the monitoring circuit comprising:
an oscillating unit comprising a first monitoring end and a second monitoring end, wherein the first monitoring end is configured to be electrically connected to the ESD protection device and the second monitoring end is configured to be electrically connected to the ground line, wherein the oscillating unit is configured to output an oscillating signal in a case that the first monitoring end is not electrically connected to the ESD protection device, or the ESD protection device is not contacted to the user's body, or the second monitoring end is not electrically connected to the ground line, or the ground line is not connected to the ground, and wherein the oscillating unit is configured to output a DC voltage signal in a case that the first monitoring end is electrically connected to the ESD protection device, and the ESD protection device is contacted to the user's body, and the second monitoring end is electrically connected to the ground line, and the ground line is connected to the ground; a signal processing unit electrically connected to the oscillating unit, configured to receive the oscillating signal and to output a first voltage according to the oscillating signal if the signal outputted by the oscillating unit is the oscillating signal wherein the signal processing unit comprises a dividing subunit configure to divide a supply voltage according to the oscillating signal, so as to output the first voltage; a dividing unit electrically connected to the second monitoring end, configured to provide an electrostatic ground voltage to the second monitoring end and a reference voltage; and a comparator electrically connected to the signal processing unit and the dividing unit, configured to co pare the first voltage and the reference voltage and to correspondingly output an alarm signal when the first voltage becomes smaller than the reference voltage.