Patent ID: 7902841
Filing Date: 2011-03-08
Classification: H03K

Abstract:
1. Arrangement for monitoring an object for changes in a field surrounding the object, comprising; at least one sensor-active region associated with the object, at least one measurement path with an associated driver for applying a determined or determinable variable in the sensor-active region, at least one receiver for detecting a variable applied by the drivers and changes in the variable in the field surrounding the object in the sensor-active region, a circuit connected downstream of the receiver for determining changes in a field surrounding the object and for generating at least one of a control and measurement signal using the changes detected, wherein to detect changes in the variable in the field surrounding the object, in addition to the at least one measurement path, there is provided at least one further measurement path or a reference section with an associated driver, wherein there is provided a clock circuit for switching on at intervals of time each of the measurement paths or the measurement path and the reference path, wherein there is provided a regulating device for regulating the at least one variable introduced by the drivers into at least one of the measurement paths and the reference path in response to changes in the variable in the field, with the result that at the receiver average the same amplitude of the variable passes from the drivers and the sensor-active region to the receiver from each of the measurement paths, and wherein the sensor-active region is coupled with high resistance at least to the drivers.