An 180 nm Four-Port Multi-Directional ASIC for Holonomic Features Extraction of Colloidal Systems

The emergence of liquid electronic devices and liquid artificial synapses drew the limelight of unconventional computing due to its bio-inspired mimicking of synaptic plasticity and nonlinearity. In this work, we have designed a custom chip using 180 nm CMOS technology that can program the colloid sample and feature a fast 3.2 ms read-cum-inference with a read frequency at RF in the range between 5 MHz and 1.67 GHz. The implemented 4-port colloidal system is multi-directional (programming, reading and inferring the state can be carried out across any port independently) and highly modular (similar CMOS structures can be replicated to design an N-port colloidal system) in nature. A custom-designed PCB and the FPGA driver complete the digital control for the characterization of the colloid. Finally, using our chip, this work demonstrates holonomic measurements using a magnetite (Fe3O4) based ferrofluid stabilized with oleic acid and hosted in a sealed vial.