DC voltage conversion circuit and liquid crystal display device including the same

A liquid crystal display (LCD) device, comprising a DC voltage conversion circuit, wherein the DC voltage conversion circuit comprises:

• a booster circuit having a booster input terminal and a booster output terminal, where the booster input terminal receives a first voltage, and the booster circuit converts the first voltage into a second voltage, and provides the second voltage to a VGH line of the LCD device through the booster output terminal;
• and
• a protection circuit comprising a detection circuit, a first feedback circuit, a first adjustment circuit, a second adjustment circuit, and a second feedback circuit, where the first feedback circuit has an input terminal electrically connected to the booster output terminal, and an output terminal electrically connected a VGH line of the LCD device, the second feedback circuit has an end electrically connected to the booster output terminal and another end to ground;
• when the booster circuit is not under Electrical Over Stress (EOS) test, the detection circuit detects the VGH line's voltage, and obtains a first detection voltage accordingly;
• the first detection voltage is output through an output terminal of the detection circuit;
• the first adjustment circuit compares the first detection voltage and a reference voltage, and produces a first signal based on the comparison result;
• the first signal is for adjusting an equivalent resistance of the first feedback circuit to a first equivalent resistance;
• the second adjustment circuit produces a second signal based on the first detection voltage;
• the second signal is for adjusting an equivalent resistance of the second feedback circuit to a second equivalent resistance;
• when the booster circuit is under EOS test, test signal is applied to the booster output terminal;
• the detection circuit detects the VGH line's voltage, and obtains a second detection voltage accordingly;
• the second detection voltage is output through the output terminal of the detection circuit;
• the first adjustment circuit compares the second detection voltage and the reference voltage, and produces a third signal based on the comparison result;
• the third signal is for adjusting an equivalent resistance of the first feedback circuit to a third equivalent resistance;
• the second adjustment circuit produces a fourth signal based on the second detection voltage;
• the fourth signal is for adjusting an equivalent resistance of the second feedback circuit to a fourth equivalent resistance;
• when the first feedback circuit is adjusted to have the third equivalent resistance and the second feedback circuit is adjusted to have the fourth equivalent resistance, the voltage on the VGH line becomes the first detection voltage.