Abstract: A capacitive keyboard that can detect a key that has been depressed and the depressed amount thereof with high accuracy is provided. The capacitive keyboard includes a drive circuit 11 that alternatively switches the voltage of each of drive lines M from an L-level to an H-level, a sensing circuit 12 that is connected to each of sensing lines N and that selects one of the sensing lines N to detect the voltage generated in the selected sensing line, and a control circuit 15. The control circuit 15 includes a storage unit 44 including storage areas corresponding to keys, a storage control unit 42 that acquires the voltage generated in the sensing line and that stores the acquired voltage in a storage area corresponding to a key, and a correction unit 43 that corrects, if one of the keys is operated, the voltage generated as a result of an operation of the one of the keys by using voltages stored in storage areas corresponding to other keys.

Abstract: A capacitive keyboard that can detect a key that has been depressed and the depressed amount thereof with high accuracy is provided. The capacitive keyboard includes a drive circuit 11 that alternatively switches the voltage of each of drive lines M from an L-level to an H-level, a sensing circuit 12 that is connected to each of sensing lines N and that selects one of the sensing lines N to detect the voltage generated in the selected sensing line, and a control circuit 15. The control circuit 15 includes a storage unit 44 including storage areas corresponding to keys, a storage control unit 42 that acquires the voltage generated in the sensing line and that stores the acquired voltage in a storage area corresponding to a key, and a correction unit 43 that corrects, if one of the keys is operated, the voltage generated as a result of an operation of the one of the keys by using voltages stored in storage areas corresponding to other keys.

Abstract: A capacitive keyboard that can detect a key that has been depressed and the depressed amount thereof with high accuracy is provided. The capacitive keyboard includes a drive circuit 11 that alternatively switches the voltage of each of drive lines M from an L-level to an H-level, a sensing circuit 12 that detects the voltage generated in each of sensing lines N, and a control circuit 15 that detects, on the basis of the voltage value detected by the sensing circuit 12, the key that has been operated and the operation amount of the operated key. The sensing circuit 12 includes a peak hold circuit 32 that holds the peak value of the voltage that is input from a sensing line N over a predetermined period and an A/D conversion circuit 33 that converts the voltage held by the peak hold circuit 32 into a multi-stage digital voltage value.