TID Response of an Analog In-Memory Neural Network Accelerator.

A vector-matrix multiply (VMM) characterization chip was designed and fabricated in 350nm CMOS, including pulsers and a 10-bit analog to digital converter. The response of total ionizing dose (TID) was assessed using gamma radiation from a Cobalt-60 source. Inference was performed in situ during irradiation and VMMs computed by the accelerator were measured at increasing TID levels. Experimental results were used to create a circuit model, which was enabled a neural network accuracy simulation with CrossSim. Accuracy degradation on the CIFAR-10 task was a function of network architecture and was significantly reduced following >150 krad exposure.