Buffer circuit, panel module, and display driving method

A buffer circuit, comprising:

• a first polarity gamma buffer having a first power receiving terminal for receiving a first supply voltage and having a second power receiving terminal for receiving a second supply voltage, to output a first reference voltage to at least one first resistance string;
• a supply voltage output circuit;
• and
• a second polarity gamma buffer having a third power receiving terminal for receiving the second supply voltage and having a fourth power receiving terminal for receiving a third supply voltage, to output a second reference voltage to a second resistance string, wherein the third supply voltage is less than the second supply voltage;
• wherein the supply voltage output circuit comprises a medium voltage gamma buffer having an output terminal and a capacitor coupled to the output terminal of the medium voltage gamma buffer, and the medium voltage gamma buffer comprises a first power supply for receiving the first supply voltage, a second power supply for receiving the third supply voltage and an output supply that outputs the second supply voltage, and each of the second power receiving terminal and the third power receiving terminal is coupled to the output terminal of the medium voltage gamma buffer,
• wherein the supply voltage output circuit provides the second supply voltage which is different from a ground voltage, and
• wherein the output terminal of the medium gamma buffer is connected to an inverting input terminal of the medium voltage gamma buffer.

A driving device, comprising:

• a first resistance string;
• a second resistance string;
• a first polarity gamma buffer having a first power receiving terminal for receiving a first supply voltage and having a second power receiving terminal for receiving a second supply voltage, to output a first reference voltage to the first resistance string, wherein the second supply voltage is different from a ground voltage;
• a supply voltage output circuit for providing the second supply voltage;
• a second polarity gamma buffer having a third power receiving terminal for receiving the second supply voltage and having a fourth power receiving terminal for receiving a third supply voltage, to output a second reference voltage to the second resistance string, wherein the third supply voltage is less than the second supply voltage;
• and
• a driving circuit for driving a panel according to the first reference voltage and the second reference voltage;
• wherein the supply voltage output circuit comprises a medium voltage gamma buffer having an output terminal and a capacitor coupled to the output terminal of the medium voltage gamma buffer, and the medium voltage gamma buffer comprises a first power supply for receiving the first supply voltage, a second power supply for receiving the third supply voltage and an output supply that outputs the second supply voltage, and each of the second power receiving terminal and the third power receiving terminal is coupled to the terminal of the medium voltage gamma buffer, and
• wherein the output terminal of the medium gamma buffer is connected to an inverting input terminal of the medium voltage gamma buffer.