NEURAL NETWORK UNIT WITH SHARED ACTIVATION FUNCTION UNITS

A neural network unit includes first and second memories that hold rows of respective N weight and data words and provides a row of them to N corresponding neural processing units (NPU), respectively. The N NPUs each have an accumulator and an arithmetic unit that performs a series of multiply operations on pairs of weight words and data words received from the first and second memories to generate a series of products. The arithmetic unit also performs a series of addition operations on the series of products to accumulate an accumulated value in the accumulator. Activation function units (AFU) are each shared by a corresponding plurality of the N NPUs. Each AFU, in a sequential fashion with respect to each NPU of the corresponding plurality of the N NPUs, receives the accumulated value from the NPU and performs an activation function on the accumulated value to generate a result.