PROGRAMMABLE CMOS CURRENT COMPARATOR-CIRCUIT FOR ANALOG VLSI NEURAL NETWORKS UTILIZING IDENTICAL SMALL-DIMENSION MOS-TRANSISTORS

A programmable CMOS current comparator circuit is presented which empl oys seven identical small-dimension MOS transistors, and whose thresho ld current is adjustable without the need to change any of the MOS tra nsistors. Using transistors with W/L of 2/0.6 mum and a 5 V supply vol tage, the comparator can be programmed to detect currents over the ran ge from 50 nA to 550 muA. With W/L of 3/0.6 mum and a 3.3 V supply vol tage, the programmable range is from 20 nA to 365 muA. Simulations for these configurations indicate that the circuit has propagation delays of 4.125 ns and 4.08 ns, respectively.