To provide a switch opening/closing detection device which detects opening/closing states of a plurality of switches with the minimum number of signal lines with a higher reliability than a conventional one.
The switch opening/closing detection device 1 is equipped with: the plurality of switches SW1-SWn; a plurality of capacitors C1-Cn; a resistive element R; and a signal processing part 10. The plurality of switches SW1-SWn are arranged in parallel to each other between a first node ND1 and a ground node GND. The plurality of capacitors C1-Cn correspond to the plurality of switches SW1-SWn respectively, are arranged in series to the corresponding switches, and have capacity values different from each other. The resistive element R is arranged between the first node ND1 and a second node ND2. The signal processing part 10 applies a voltage on the second node ND2, and detects the opening/closing states of the plurality of switches SW1-SWn, based on a change of a voltage of the first node ND1 caused by the application of the voltage to the second node ND2.
| JP2000306451A | 2000-11-02 | |||
| JP2005346550A | 2005-12-15 | |||
| JPH0636643A | 1994-02-10 |
Toshio Morita
Yoshihei Nakamura
Yutaka Horii
Masayuki Sakai
Nobuo Arakawa
Masato Sasaki