Low-voltage electronics for the stimulation of biological neural networks using fully complementary BiCMOS circuits

This paper describes low-voltage neural stimulating circuitry developed using fully complementary BiCMOS (FC-BiCMOS) process technology for providing charge-balanced bipolar stimulating currents to tissue in the central nervous system. The electronics features an FC-BiCMOS buffer, a 7-b biphasic current-output digital-to-analog converter, a 14-b frequency divider, a nonoverlapping two-phase clock generator, and an auto timeout safety scheme while driving any two of eight selected sites from 0 to ±126 μA with ±2 μA resolution. The circuit area is 1.6 mm² in 3-μm features. Micropower circuit techniques allow the probe to dissipate <10 μW in standby and operate at 10 MHz from ±2.5 V supplies