Proximity sensor
US7952366B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 2008 |
| Grant date | May 31, 2011 |
| Priority date | — |
| Expiry date | Aug 3, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2217/960725
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A capacitive touch sensor providing an automatic switch-off function for an apparatus in which the sensor is incorporated is provided. The sensor includes a sensing element coupled to a capacitance measurement circuit for measuring the capacitance of the sensing element. A control circuit is operable to determine from the capacitance measurement whether an object is in proximity with the sensor. The determined presence of an object may he used to toggle a function of the apparatus. Furthermore, when it is determined that an object has not been in proximity with the sensor for a predetermined time duration, an output signal for switching off the apparatus is provided. The predetermined time duration may be selected from a number of predefined time durations, or may be programmed using a resistor-capacitor network. Pulses may be applied to the control circuit to override features of the automatic switch-off functionality.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.