发明授权
US07168320B2 Method and unit for sensing physical quantity using capacitive sensor
有权
使用电容式传感器感测物理量的方法和单元
- 专利标题: Method and unit for sensing physical quantity using capacitive sensor
- 专利标题(中): 使用电容式传感器感测物理量的方法和单元
-
申请号: US10895978申请日: 2004-07-22
-
公开(公告)号: US07168320B2公开(公告)日: 2007-01-30
- 发明人: Minoru Murata , Takaaki Kawai
- 申请人: Minoru Murata , Takaaki Kawai
- 申请人地址: JP Kariya
- 专利权人: Denso Corporation
- 当前专利权人: Denso Corporation
- 当前专利权人地址: JP Kariya
- 代理机构: Posz Law Group, PLC
- 优先权: JP2003-279960 20030725
- 主分类号: G01P15/125
- IPC分类号: G01P15/125
摘要:
A physical quantity (e.g., acceleration) sensing unit is provided. In this unit, a capacitive sensor has first and second fixed electrodes and a physical-quantity-sensitive movable electrode disposed between the first and second fixed electrodes. An adjusting circuit first adjusts a first bias voltage applied between the first fixed electrode and the movable electrode and a second voltage applied between the movable electrode and the second fixed electrode so that the movable electrode is brought into contact with either the first or second fixed electrode. The adjusting circuit then adjusts the first and second bias voltages to return the movable electrode to its original position. A detecting circuit detects an output on a capacitance relationship among the first and second fixed electrodes and the movable electrode. The output is subjected to determination of whether or not the output is out of order, when tested.