A very low power 0.7 V subthreshold fully programmable Gaussian function generator

In this paper, an analog current mode implementation of a fully programmable Gaussian function generator (GFG) is presented. The subthreshold current mode circuits enable the design to operate at very low supply voltage and consume very little power. Translinear loop technique is used to generate high precision quadratic current and a single PMOS transistor is used to generate the Gaussian profile. The peak, standard deviation, and mean of the Gaussian profile can be freely programmed. An accurate second order Gaussian profile can be generated by two identical Gaussain circuits with the translinear loop at twice the speed of the cascaded Gaussian circuits. Simulation results show that the circuit consumes only 2 μW at maximum at 0.7 V in 0.18 μm CMOS technology.