Thomas W. Stouffer,Daniel Aghassian,Lev Freidin,Vasily Dronov
申请号：
US13900877
公开号：
US20140025139A1
申请日:
2013.05.23
申请国别(地区):
US
年份:
2014
代理人:
摘要：
Receiver and demodulation circuitry for an external controller for an implantable medical device is disclosed. The circuitry comprises two high Quality-factor band pass filters (BFPs) connected in series. Each BFP is tuned to a different center frequency, such that these center frequencies are outside the band of frequencies transmitted form the IMD. The resulting frequency response is suitably wide to receive the band without attenuation, but sharply rejects noise outside of the band. The resulting filtered signal is input to a comparator to produce a square wave of the filtered signal, which maintains the frequencies of the received signal and is suitable for input to a digital input of a microcontroller in the external controller. Demodulation of the square wave occurs in the microcontroller, and involves assessing the time between transitions in the square wave. These transmission timings are compared to expected transition times for the logic states in the transmitted data. The results of these comparisons are stored and filtered to remove noise and to recover the transmitted data.
