A compact spike-timing-dependent-plasticity circuit for floating gate weight implementation

作者：Smith A W; McDaid L J; Hall S^*

来源：Neurocomputing, 2014, 124: 210-217.

DOI：10.1016/j.neucom.2013.07.007

• Spike timing dependent plasticity
• Neural networks
• Floating gate
• MOSFET

Spike timing dependent plasticity (STOP) forms the basis of learning within neural networks. STDP allows for the modification of synaptic weights based upon the relative timing of pre- and post-synaptic spikes. A compact circuit is presented which can implement STOP, including the critical plasticity window, to determine synaptic modification. A physical model to predict the time window for plasticity to occur is formulated and the effects of process variations on the window is analyzed. The STDP circuit is implemented using two dedicated circuit blocks, one for potentiation and one for depression where each block consists of 4 transistors and a polysilicon capacitor. SpectreS simulations of the back-annotated layout of the circuit and experimental results indicate that STOP with biologically plausible critical timing windows over the range from 10 is to 100 ms can be implemented. Also a floating gate weight storage capability, with drive circuits, is presented and a detailed analysis correlating weights changes with charging time is given.

• 出版日期2014-1-26