IEEE Trans Biomed Circuits Syst. 2010 Oct;4(5):311-9. doi: 10.1109/TBCAS.2010.2055157.
A neuromorphic analog chip is presented that is capable of implementing massively parallel neural computations while retaining the programmability of digital systems. We show measurements from neurons with Hopf bifurcations and integrate and fire neurons, excitatory and inhibitory synapses, passive dendrite cables, coupled spiking neurons, and central pattern generators implemented on the chip. This chip provides a platform for not only simulating detailed neuron dynamics but also uses the same to interface with actual cells in applications such as a dynamic clamp. There are 28 computational analog blocks (CAB), each consisting of ion channels with tunable parameters, synapses, winner-take-all elements, current sources, transconductance amplifiers, and capacitors. There are four other CABs which have programmable bias generators. The programmability is achieved using floating gate transistors with on-chip programming control. The switch matrix for interconnecting the components in CABs also consists of floating-gate transistors. Emphasis is placed on replicating the detailed dynamics of computational neural models. Massive computational area efficiency is obtained by using the reconfigurable interconnect as synaptic weights, resulting in more than 50 000 possible 9-b accurate synapses in 9 mm(2).
提出了一种神经拟态模拟芯片，它能够在保留数字系统可编程性的同时实现大规模并行神经计算。我们展示了具有 Hopf 分岔和积分-点火神经元、兴奋性和抑制性突触、被动树突电缆、耦合尖峰神经元和中央模式发生器的神经元的测量结果，这些都在芯片上实现。该芯片不仅为模拟详细的神经元动力学提供了平台，还使用相同的平台与实际细胞接口，例如在动态钳位中应用。有 28 个计算模拟块 (CAB)，每个 CAB 都由具有可调参数的离子通道、突触、胜者全拿元件、电流源、跨导放大器和电容器组成。还有另外四个 CAB 具有可编程偏置发生器。可编程性是通过使用带有片上编程控制的浮栅晶体管来实现的。用于连接 CAB 中组件的开关矩阵也由浮栅晶体管组成。重点是复制计算神经模型的详细动态。通过将可重构互连用作突触权重，获得了大量计算面积效率，在 9 平方毫米 (2) 的面积上实现了超过 50000 个 9 位精确的突触。
