The invention provides a design method and a use method of a
variable precision calculation unit applied to a quantization neural network convolutional layer, and the method comprises the steps: carrying out the shift operation of a vector with the precision of 1, and determining the shift digit, dimension and number of an operation
basic block; and arranging operation basic blocks and then connecting the operation basic blocks by using an
adder tree to form an array to obtain a fusion calculation unit with
variable precision. According to the actual precision of the activation value and the
weight value of the current convolutional layer, a variable-precision fusion calculation unit array is configured, and all columns of fusion calculation units carry out parallel calculation; and after the operation of the current convolutional layer is completed, according to the data precision of the next convolutional layer, the two-dimensional array is reconfigured, and the operation of all the convolutional
layers is completed by parity of reasoning. The problems that in the prior art, an operation unit is prone to causing waste of calculation resources in
convolution operation smaller than 4 bits, different quantization bit widths cannot be flexibly and dynamically adopted to process data according to the actual situation of a
convolution layer, and the
resource utilization rate and the calculation efficiency cannot be improved are solved.