Compact Digital-Controlled Neuromorphic Circuit with Low Power Consumption

A highly compact and low power consumption neuromorphic circuit with digital control signals which achieves the functional properties of biological neuron and synapse is proposed in this paper. The excitatory or inhibitory synapse could convert pre-synaptic spikes to current to charge or discharge the neuron. During the presence of the post-synaptic current (PSC), the ring oscillator (RO) based neuron is capable of generating regular spiking (RS), intrinsically bursting (IB) or fast spiking (FS) behaviors, which are controlled by digital signals. Based in a 65-nm CMOS technology, the silicon area of the excitatory synapse, the inhibitory synapse and the neuron is only 6.8 mu m(2), 1.4 mu m(2) and 20.8 mu m(2), respectively. It is beneficial to the increasing scale of neural networks. Moreover, the overall power consumption of the circuit is only 418 nW.