High-voltage compliant microelectrode array drivers for intracortical microstimulation

作者：Hasanuzzaman Md^*; Raut Rabin; Sawan Mohamad

来源：International Journal of Circuit Theory and Applications, 2016, 44(3): 660-682.

DOI：10.1002/cta.2099

• visual intracortical microstimulation
• implantable biomedical devices
• high-impedance microelectrode array driver
• high-voltage compliance
• switch-matrix
• microelectrode array

We present in this paper two low-power high-impedance microelectrode array drivers (MEDs) dedicated for visual intracortical microstimulation. These output stages of a new microstimulator are highly configurable and able to deliver higher compliance voltage (20V for anodic and cathodic phases) across microelectrode-tissue interface impedance compared with previously reported designs. Each MED is featured with a high-voltage switch-matrix, 3.3V/20V current mirrors, an on-chip 32-bit serial-in parallel-out shift register, and the new forbidden state logic circuits. Both systems are able to deliver eight bipolar or 16 monopolar stimulation simultaneously. The first MED is able to deliver one stimulation current level and the second one provides four different current amplitudes simultaneously to 16 electrodes. Two microchips have been designed and fabricated using Teledyne DALSA 0.8 mu m 5V/ 20v double-diffused metal-oxide-semiconductor field-effect transistor (Teledyne DALSA Semiconductor, Bromont, Quebec, Canada) technology to meet the required high-voltage compliance. The nominal values of largest supply voltages are +/- 10V. The maximum stimulation current per input channel is 400A and per output channel through an emulated microelectrode impedance of 100k is 100A. The measured output compliance voltage is 10V/phase (anodic or cathodic) for the specified supply voltages. Increment of supply voltages to +/- 13V allows 220A stimulation current per output channel enhancing the output compliance voltage up to 20V/phase. The measured quiescent power consumptions of the proposed microelectrode array drivers are 316 and 735W, respectively. Post-layout simulation and measurement results of two MEDs and comparison with other designs have been reported in this paper.

• 出版日期2016-3