SENSOR DEVICE FOR A DRUG DELIVERY DEVICE

摘要

A sensor device configured to be removably attached to a drug delivery device, the sensor device comprising an array of conducting elements each forming part of a respective resonant circuit and each operable to have a signal applied to it. The drug delivery device has a first movable element which supports a conductive region and which is configured to move along a path parallel to a longitudinal axis of the drug delivery device. When the sensor device is attached to the drug delivery device, the array of conducting elements are arranged such that each resonant circuit is operable to output a signal indicative of the proximity of the conductive region supported on the first moveable element to the respective conducting element of each resonant circuit. The sensor device further comprises circuitry configured to receive the signals output from the resonant circuit and, based on the received signals, to determine information associated with a location along the path of the first movable element.