Implementation of a telemetric-monitoring system in a cochlear implant

Presents a telemetric-monitoring system which is incorporated in a cochlear implant. This system allows (1) the measurement of voltages at active channels determining the electrode impedances, (2) the measurement of voltages at passive channels for the estimation of the field distribution along the electrode array, and (3) the measurement of the implant supply voltage within a voltage range of 0.1 V<U_m <5.5 V, the resolution is 6 bit. The measurement information is transcutaneously sent to the outside by means of load modulation. The same RF-channel which provides the implant with for external transmission, the value of the measured stimulation data and power can be employed in the implementation of the system, thus eliminating the need for an additional RF-channel