Reference voltage generation circuit, display drive circuit, display device and reference voltage generation method

A reference voltage generation circuit which generates multi-valued reference voltages for generating a gray scale value corrected by gamma correction based on gray scale data, the reference voltage generation circuit comprising:

• a ladder resistor circuit including a plurality of resistor circuits connected in series, and outputting voltages of first to i-th division nodes (“i” is an integer larger than or equal to 2) as first to i-th reference voltages, the first to i-th division nodes being formed by dividing the ladder resistor circuit by the resistor circuits;
• a first switching circuit inserted between a first power source line supplied with a first power source voltage and one end of the ladder resistor circuit;
• and
• a second switching circuit inserted between a second power source line supplied with a second power source voltage and the other end of the ladder resistor circuit,
• wherein on/off state of the first and second switching circuits are controlled based on first and second switching control signals.