Coordinate input device, and a display device including the same

PROBLEM TO BE SOLVED: To provide a capacitance detection circuit for detecting a minute input capacitance by a high signal noise rate, in a coordinate input device for detecting a capacitance. SOLUTION: The capacitance detection circuit is configured of: a capacitance sensor electrode; a switch element SA for applying a fixed potential to the capacitance sensor electrode to detect a capacitance related to the capacitance sensor electrode; a switch element SB for transferring charges stored in the capacitance sensor electrode; and an integration circuit for detecting charges to be transferred from the capacitance sensor electrode through the switch element SB. A voltage source which supplies a fixed potential is connected through the switch element SA to the capacitance sensor electrode, and the capacitance sensor electrode is connected through the switch element SB to the input terminal of the integration circuit. The switch element SC and an adjustment capacitance Ca to be short-circuited to the reference level of the integration circuit are connected to the input terminal of the integration circuit of the capacitance detection circuit, and a signal ADJ for adjustment is applied to the other terminal of the adjustment capacitance Ca. COPYRIGHT: (C)2011,JPO&INPIT