A dual-mode low-noise nanosensor front-end with 155-dB dynamic range

A novel integrated current measurement system with ultra wide dynamic range is presented and fabricated in a 180-nm CMOS technology. Its dual-mode design provides concurrent voltage and frequency outputs, without requiring an external clock source. An integrator-differentiator core provides a voltage output with a noise floor of 11.6 f Arms /√Hz and a measurement bandwidth of 1.4 MHz. This is merged with an asynchronous current-to-frequency converter (CFC), which generates an output frequency linearly proportional to the input current. Together, the voltage and frequency outputs yield a current measurement range of 155-dB, spanning from 204 fA to 11.6 μA. The proposed architecture's low noise, wide bandwidth, and wide dynamic range make it ideal for measurements of ion channels, nanopores, tunneling junctions, and other nanosensors.