| CPC H02H 7/20 (2013.01) [G01R 31/2849 (2013.01)] | 7 Claims |

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1. A protection circuit for protecting an electronic device under a high temperature reverse bias (HTRB) test, the protection circuit comprising:
a switch configured to connect/disconnect the protection circuit to/from the electronic device based on a switching signal;
a current-sensing circuit configured to sense a drain-source leakage current flowing through a drain-source junction of the electronic device and generate a current-sensing signal; and
a driving circuit configured to receive the current-sensing signal from the current-sensing circuit and generate a driving signal for switching on/off the switch, and when the current-sensing signal is higher than a reference voltage, the driving circuit is configured to transmit the driving signal to the switch to control the switch to disconnect the protection circuit from the electronic device, such that a drain source leakage current is blocked by the switch;
wherein:
the switch has a first conduction terminal connected to the electronic device;
the current-sensing circuit has an input terminal connected to a second conduction terminal of the switch and a ground terminal connected to a negative terminal of a power supply; and
the driving circuit has an input terminal connected to an output terminal of the current-sensing circuit, a ground terminal connected to the negative terminal of the power supply, and an output terminal connected to a control terminal of the switch;
wherein the driving circuit comprises:
a comparator configured to receive the current-sensing signal and compare the current-sensing signal with the reference voltage to generate a comparison output signal;
an internal reference voltage supply configured to provide the reference voltage to the comparator; and
a latch configured to receive the comparison output signal and generate the driving signal;
wherein the switch is a normally-off switch;
wherein the comparator of the driving circuit has a non-inverting input terminal connected to an input terminal of the driving circuit and an inverting input terminal connected to the internal reference voltage supply; and the latch of the driving circuit is a rising-edge triggered latch having a reset terminal connected to an output terminal of the comparator and an inverted output terminal connected to the output terminal of the driving circuit; or
the comparator of the driving circuit has a non-inverting input terminal connected to the internal reference voltage supply and an inverting input terminal connected to an input terminal of the driving circuit; and the latch of the driving circuit is a falling-edge triggered latch having a reset terminal connected to an output terminal of the comparator and an inverted output terminal connected to the output terminal of the driving circuit.
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