This paper proposes a miniaturized optoelectronic system suitable for the optical stimulation of genetically engineered retinal ganglion cells (RGCs) and focuses upon the synthesis and performance characteristics of a key circuit component needed for the programmable stimulator chip of the system: a wide tuning range voltage-controlled oscillator (VCO). The paper elaborates the synthesis and performance of a novel OTA structure which is used for the realisation of the needed wide tuning range VCO. The VCO has been designed and fabricated in AMS 0.35mum CMOS technology. Simulation results reveal a tuning range of more than 6 decades (70mHz to 0.2MHz).
['Yan Huang', 'Emmanuel M. Drakakis', 'Chris Toumazou']
A Wide Tuning Range CMOS Oscillator for an Optoelectronic Retinal Prosthesis System