A novel HV-switch scheme with gate-source overvoltage protection for bidirectional neural interfaces

In this paper a novel high-voltage switch with gate-source overvoltage protection is presented for use in high voltage bidirectional neural interfaces. The proposed switch can tolerate the voltage difference up to 120V between its terminals. The control circuit guarantees the operation of HV transistors in the Safe Operation Area (SOA) by use of the proposed switched voltage follower. The switch can be controlled with low voltage control signals compatible with standard CMOS logic levels. The simulation of the switch performance was carried out with AMS HV 0.35 μm Design Kit.