A linearized current stimulator for deep brain stimulation

This paper develops the front end of the stimulator which is applied in the implantable deep brain stimulation (DBS) for the therapy of Parkinson´s disease. This stimulator adopts the low power switched-capacitor DAC accompanying with voltage-to-current transconductance amplifiers to obtain the adjustable output currents. The proposed distortion cancellation technique improves the linearity of the current stimulator. Multiple transconductance amplifiers sharing a single DAC save the circuit area. The biphasic stimulation waveform is generated from the bridge switching technique and the programmable pulse. This stimulation circuit provides the 0~165 μA current for a typical loading of 10 kΩ, 8~120 μs pulse width, and 126~244 Hz frequencies with a 0.35 μm CMOS technology at 3.3 V supply voltage.