Level shifter

A level shifter comprising:

• a first transistor, having a first terminal configured to receive a first high voltage, a second terminal configured to output a first output voltage, and a control terminal;
• a second transistor, having a first terminal configured to receive the first high voltage, a second terminal configured to output a second output voltage and coupled to the control terminal of the first transistor, and a control terminal coupled to the second terminal of the first transistor;
• a first cross-voltage relief circuit having a first terminal coupled to the second terminal of the first transistor, and a second terminal, wherein the first cross-voltage relief circuit is configured to conduct according to at least one bias voltage to provide a voltage drop between the first terminal and the second terminal of the first cross-voltage relief circuit;
• a third transistor having a first terminal coupled to the second terminal of the first cross-voltage relief circuit, a second terminal configured to receive a first input voltage, and a control terminal configured to receive a second high voltage;
• a second cross-voltage relief circuit having a first terminal coupled to the second terminal of the second transistor, and a second terminal, wherein the second cross-voltage relief circuit is configured to conduct according to the at least one bias voltage to provide a voltage drop between the first terminal and the second terminal of the second cross-voltage relief circuit;
• and
• a fourth transistor having a first terminal coupled to the second terminal of the second cross-voltage relief circuit, a second terminal configured to receive a second input voltage, and a control terminal configured to receive the second high voltage,
• wherein the first high voltage is higher than the second high voltage, and the first input voltage is complementary to the second input voltage, and
• wherein the first input voltage is at the second high voltage or a low voltage lower than the second high voltage.