A Tri-State FSK Demodulator for Asynchronous Timing of High-Rate Stimulation Pulses in Wireless Implantable Microstimulators

Author

Ghovanloo, Maysam ; Najafi, Khalil

Author_Institution

Dept. of Electr. & Comput. Eng., North Carolina State Univ., Raleigh, NC

fYear

2005

fDate

16-19 March 2005

Firstpage

116

Lastpage

119

Abstract

A tri-state FSK modulation protocol and demodulator circuit have been developed and explained in this paper for wireless data rates as high as the carrier frequency. This method is used for asynchronous timing of high-rate stimulation pulses in wireless implantable microstimulators to improve the timing resolution of the stimulation pulses from one data-frame period to only one carrier cycle period. The demodulator circuit is used in a 16-site wireless active stimulating microprobe fabricated in the University of Michigan 3-mum, 1-metal, 2-poly, N-epi, BiCMOS process, occupying 1.17 mm² of the probe active area. The FSK demodulator circuit is simulated up to 2.5 Mega bits per second (b/s) and tested up to 300 kb/s

Keywords

demodulators; frequency shift keying; prosthetic power supplies; BiCMOS process; asynchronous timing; high-rate stimulation pulses; modulation protocol; timing resolution; tri-state FSK demodulator; wireless active stimulating microprobe; wireless implantable microstimulators; Bandwidth; Circuits; Communication system control; Demodulation; Frequency shift keying; Implants; Probes; Pulse generation; Shift registers; Timing;

fLanguage

English

Publisher

ieee

Conference_Titel

Neural Engineering, 2005. Conference Proceedings. 2nd International IEEE EMBS Conference on

Conference_Location

Arlington, VA

Print_ISBN

0-7803-8710-4

Type

conf

DOI

10.1109/CNE.2005.1419567

Filename

1419567