Flash-based programmable nonlinear capacitor for switched-capacitor implementations of neural networks

The use of flash devices for both analog storage and analog computation can result in highly efficient switched-capacitor implementations of neural networks. The standard flash device suffers from severe limitations in this application due to relatively large parasitic overlap capacitances. This paper introduces the computational concept, circuit and architecture we are exploring as well as a novel flash-based programmable nonlinear capacitor with much improved charge domain characteristics for our application. These devices are demonstrated in a novel circuit consisting of only two devices and capable of computing a 5-bit absolute-value-of-difference at an energy consumption of less than 1 pJ.<>