Telemetry means for tissue stimulator system
US4223679A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 1979 |
| Grant date | Sep 23, 1980 |
| Priority date | — |
| Expiry date | Feb 28, 1999 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61N1/3727
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A telemetry system for use in a living tissue stimulator system in which an externally located oscillator is controlled by impedance changes in an impedance reflecting circuit located in an implantable tissue stimulator. In a first embodiment the impedance reflecting circuit is an LC circuit thereby frequency modulating the externally located oscillator and in a second embodiment it is an LR circuit thereby amplitude modulating the externally located oscillator. More specifically, the externally located oscillator drives an LC circuit in which the inductor is positioned in magnetically coupled relationship to an inductor in the impedance reflecting circuit. The externally located oscillator is chosen so that its frequency and amplitude is partially determined by the impedance of the LC circuit and the magnetically coupled impedance reflecting circuit. A parameter or signal to be telemetered, which could be in the form of a digital or an analog signal, is used to modulate an output frequency of a voltage controlled oscillator located in the implantable tissue stimulator. This frequency modulated output of the voltage controlled oscillator drives an FET switch which alters the impeda…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.