Miniaturized Wirelessly-Powered Biphasic Current Stimulator for Implantable Neurostimulation

A wirelessly-powered biphasic current stimulator is proposed and designed for implantable neurostimulation. When receiving inductive coupling power at 13.56MHz from the power amplifier, the biphasic current stimulator delivers stimulation to the output channels automatically. The stimulation amplitude ranges from 100µA to 2.5mA, and the pulse width ranges from 10µs to 620µs. This chip was fabricated in the 0.18-μm CMOS process with a silicon area of 1764μm × 1115μm. In addition, a tiny PCB of 8mm × 9mm is utilized to implement the miniaturized stimulation device with the fabricated silicon chip. With the inductive R<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X</inf> coil (L<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RX</inf>) and resonant capacitor (C<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RX</inf>), the stimulation function of this miniaturized wirelessly-powered biphasic current stimulator has been successfully verified in agar experiment.