3.3V Sub-nA Voltage Gap Readout Circuit for Memristive Biosensing in Silicon Nanowire

This paper proposes a sub-nanoampere readout circuit designed for fast and precise detection with silicon nanowire (SiNW) memristive biosensors via voltage gap measurement. Compared to traditional solutions, the proposed circuit, completed in 65 nm bulk CMOS process, significantly enhances sensitivity to the picoampere range and reduces measurement time from several minutes to one second. Comprehensive performance evaluation has been performed by considering SiNW models with different crossing behavior, including post-layout extraction (PEX) simulations. Accuracy of up to $20-30 \mathrm{mV}$ can be achieved on a particular prescaler configuration, which confirms circuit’s suitability for high-speed biosensing, real-time diagnostics and scalable integration into large sensor arrays.