Ring oscillator based sub-1V leaky integrate-and-fire neuron circuit

In this paper, a ring-oscillator (RO) based sub-1V leaky integrate-and-fire (I&F) neuron circuit is proposed, that can support user programmable refractory period and spike-frequency adaptation. Designed in CMOS 65-nm TSMC process, the neuron can operate from 0.9 V and has the unique feature that the same circuit can be programmed to operate either at biological time-scales or at accelerated time-scales. As ring-oscillators in nanometer CMOS are small compared to capacitors used in existing I&F silicon neuron (SiN), a large number of RO-based neurons can be integrated along with complex digital circuits to realize a single-chip Neuromorphic-SoC.